[ See Poise. ] An instrument to measure the weight of air. [ 1913 Webster ]

adv. [ Pref. a- + poise. ] Balanced. [ 1913 Webster ]

n. & a. [ OE. aver de peis, goods of weight, where peis is fr. OF. peis weight, F. poids, L. pensum. See Aver, n., and Poise, n. ] 1. Goods sold by weight. [ Obs. ] [ 1913 Webster ]

2. Avoirdupois weight. [ 1913 Webster ]

3. Weight; heaviness; as, a woman of much avoirdupois. [ Colloq. ] [ 1913 Webster ]

Avoirdupois weight, a system of weights by which coarser commodities are weighed, such as hay, grain, butter, sugar, tea. [ 1913 Webster ]

☞ The standard Avoirdupois pound of the United States is equivalent to the weight of 27.7015 cubic inches of distilled water at 62° Fahrenheit, the barometer being at 30 inches, and the water weighed in the air with brass weights. In this system of weights 16 drams make 1 ounce, 16 ounces 1 pound, 25 pounds 1 quarter, 4 quarters 1 hundred weight, and 20 hundred weight 1 ton. The above pound contains 7, 000 grains, or 453.54 grams, so that 1 pound avoirdupois is equivalent to 1 31-144 pounds troy. (See Troy weight.) Formerly, a hundred weight was reckoned at 112 pounds, the ton being 2, 240 pounds (sometimes called a long ton). [ 1913 Webster ]

v. t. [ imp. & p. p. Counterpoised p. pr. & vb. n. Counterpoising. ] [ OE. countrepesen, counterpeisen, F. contrepeser. See Counter, adv., and Poise, v. t. ] 1. To act against with equal weight; to equal in weight; to balance the weight of; to counterbalance. [ 1913 Webster ]

Weights, counterpoising one another. Sir K. Digby. [ 1913 Webster ]

2. To act against with equal power; to balance. [ 1913 Webster ]

So many freeholders of English will be able to beard and counterpoise the rest. Spenser. [ 1913 Webster ]

n. [ OE. countrepese, OF. contrepois, F. contrepods. See Counter, adv., and Poise, n. ] 1. A weight sufficient to balance another, as in the opposite scale of a balance; an equal weight. [ 1913 Webster ]

Fastening that to our exact balance, we put a metalline counterpoise into the opposite scale. Boyle. [ 1913 Webster ]

2. An equal power or force acting in opposition; a force sufficient to balance another force. [ 1913 Webster ]

The second nobles are a counterpoise to the higher nobility, that they grow not too potent. Bacon. [ 1913 Webster ]

3. The relation of two weights or forces which balance each other; equilibrium; equiponderance. [ 1913 Webster ]

The pendulous round eart, with balanced air,
In counterpoise. Milton. [ 1913 Webster ]

v. t. [ F. empoisonner; pref. em- + F. poison. See Poison, and cf. Impoison. ] To poison; to impoison. Shak. [ 1913 Webster ]

n. Poison. [ Obs. ] Remedy of Love. [ 1913 Webster ]

n. Poisoner. [ Obs. ] Bacon. [ 1913 Webster ]

n. [ F. empoisonnement. ] The act of poisoning. Bacon.

n. [ Equi- + poise. ] 1. Equality of weight or force; hence, equilibrium; a state in which the two ends or sides of a thing are balanced, and hence equal; state of being equally balanced; -- said of moral, political, or social interests or forces. [ 1913 Webster ]

The means of preserving the equipoise and the tranquillity of the commonwealth. Burke. [ 1913 Webster ]

Our little lives are kept in equipoise
By opposite attractions and desires. Longfellow. [ 1913 Webster ]

2. Counterpoise. [ 1913 Webster ]

The equipoise to the clergy being removed. Buckle.

v. t. [ Cf. Empoison. ] To poison; to imbitter; to impair. [ 1913 Webster ]

n. A poisoner. [ Obs. ] Beau. & Fl. [ 1913 Webster ]

n. [ Cf. Empoisonment. ] The act of poisoning or impoisoning. [ Obs. ] Pope.

v. t. To outweigh. Howell. [ 1913 Webster ]

v. t. To outweigh; to overbalance. [ R. ] Sir T. Browne. [ 1913 Webster ]

n. Preponderant weight; a counterbalance. [ R. ] Mrs. Browning. [ 1913 Webster ]

n. [ OE. pois, peis, OF. pois, peis, F. poids, fr. L. pensum a portion weighed out, pendere to weigh, weigh out. Cf. Avoirdupois, Pendant, Poise, v. ] [ Formerly written also peise. ] 1. Weight; gravity; that which causes a body to descend; heaviness. “Weights of an extraordinary poise.” Evelyn. [ 1913 Webster ]

2. The weight, or mass of metal, used in weighing, to balance the substance weighed. [ 1913 Webster ]

3. The state of being balanced by equal weight or power; equipoise; balance; equilibrium; rest. Bentley. [ 1913 Webster ]

4. That which causes a balance; a counterweight. [ 1913 Webster ]

Men of unbounded imagination often want the poise of judgment. Dryden. [ 1913 Webster ]

5. a dignified and self-confident manner; graceful composure and tact in handling difficult social situations. [ PJC ]

v. t. [ imp. & p. p. Poised, p. pr. & vb. n. Poising. ] [ OE. poisen, peisen, OF. & F. peser, to weigh, balance, OF. il peise, il poise, he weighs, F. il pèse, fr. L. pensare, v. intens. fr. pendere to weigh. See Poise, n., and cf. Pensive. ] [ Formerly written also peise. ] 1. To balance; to make of equal weight; as, to poise the scales of a balance. [ 1913 Webster ]

2. To hold or place in equilibrium or equiponderance. [ 1913 Webster ]

Nor yet was earth suspended in the sky;
Nor poised, did on her own foundation lie. Dryden. [ 1913 Webster ]

3. To counterpoise; to counterbalance. [ 1913 Webster ]

One scale of reason to poise another of sensuality. Shak. [ 1913 Webster ]

To poise with solid sense a sprightly wit. Dryden. [ 1913 Webster ]

4. To ascertain, as by the balance; to weigh. [ 1913 Webster ]

He can not sincerely consider the strength, poise the weight, and discern the evidence. South. [ 1913 Webster ]

5. To weigh (down); to oppress. [ Obs. ] [ 1913 Webster ]

Lest leaden slumber peise me down to-morrow. Shak. [ 1913 Webster ]

v. i. To hang in equilibrium; to be balanced or suspended; hence, to be in suspense or doubt. [ 1913 Webster ]

The slender, graceful spars
Poise aloft in air. Longfellow. [ 1913 Webster ]

n. (Zool.) The balancer of dipterous insects. [ 1913 Webster ]

n. [ F. poison, in Old French also, a potion, fr. L. potio a drink, draught, potion, a poisonous draught, fr. potare to drink. See Potable, and cf. Potion. ] 1. Any agent which, when introduced into the animal organism, is capable of producing a morbid, noxious, or deadly effect upon it; as, morphine is a deadly poison; the poison of pestilential diseases. [ 1913 Webster ]

2. That which taints or destroys moral purity or health; as, the poison of evil example; the poison of sin. [ 1913 Webster ]

Poison ash. (Bot.) (a) A tree of the genus Amyris (Amyris balsamifera) found in the West Indies, from the trunk of which a black liquor distills, supposed to have poisonous qualities. (b) The poison sumac (Rhus venenata). [ U. S. ] --
Poison dogwood (Bot.), poison sumac. --
Poison fang (Zool.), one of the superior maxillary teeth of some species of serpents, which, besides having the cavity for the pulp, is either perforated or grooved by a longitudinal canal, at the lower end of which the duct of the poison gland terminates. See Illust. under Fang. --
Poison gland (Biol.), a gland, in animals or plants, which secretes an acrid or venomous matter, that is conveyed along an organ capable of inflicting a wound. --
Poison hemlock (Bot.), a poisonous umbelliferous plant (Conium maculatum). See Hemlock. --
Poison ivy (Bot.), a poisonous climbing plant (formerly Rhus Toxicodendron, or Rhus radicans, now classified as Toxicodendron radicans) of North America. It is common as a climbing vine, especially found on tree trunks, or walls, or as a low, spreading vine or as a shrub. As a low vine it grows well in lightly shaded areas, recognizable by growing in clusters of three leaves. Its leaves are trifoliate, rhombic-ovate, and variously notched. Its form varies slightly from location to location, leading to some speculation that it may consist of more than one species. Many people are poisoned by it, though some appear resistant to its effects. Touching the leaves may leave a residue of an oil on the skin, and if not washed off quickly, sensitive areas of skin become reddened and develop multiple small blisters, lasting for several days to several weeks, and causing a persistent itch. The toxic reaction is due to an oil, present in all parts of the plant except the pollen, called urushiol, the active component of which is the compound pentadecylacatechol (according to Charles H. Booras). See Poison sumac. It is related to poison oak, and is also called mercury. --
Poison nut. (Bot.) (a) Nux vomica. (b) The tree which yields this seed (Strychnos Nuxvomica). It is found on the Malabar and Coromandel coasts. --
Poison oak (Bot.), a dermatitis-producing plant often lumped together with the poison ivy (Toxicodendron radicans) in common terminology, but more properly distinguished as the more shrubby Toxicodendron quercifolium (syn. Toxicodendron diversilobum), common in California and Oregon. Opinion varies as to whether the poison oak and poison ivy are only variants of a single species. See poison ivy, above. --
Poison sac. (Zool.) Same as Poison gland, above. See Illust. under Fang. --
Poison sumac (Bot.), a poisonous shrub formerly considered to be of the genus Rhus (Rhus venenata), but now classified as Toxicodendron vernix; -- also called poison ash, poison dogwood, and poison elder. It has pinnate leaves on graceful and slender common petioles, and usually grows in swampy places. Both this plant and the poison ivy (Toxicodendron radicans, formerly Rhus Toxicodendron) have clusters of smooth greenish white berries, while the red-fruited species of this genus are harmless. The tree (Rhus vernicifera) which yields the celebrated Japan lacquer is almost identical with the poison sumac, and is also very poisonous. The juice of the poison sumac also forms a lacquer similar to that of Japan. [ 1913 Webster +PJC ]

Syn. -- Venom; virus; bane; pest; malignity. -- Poison, Venom. Poison usually denotes something received into the system by the mouth, breath, etc. Venom is something discharged from animals and received by means of a wound, as by the bite or sting of serpents, scorpions, etc. Hence, venom specifically implies some malignity of nature or purpose. [ 1913 Webster ]

v. t. [ imp. & p. p. Poisoned p. pr. & vb. n. Poisoning. ] [ Cf. OF. poisonner, F. empoissoner, L. potionare to give to drink. See Poison, n. ] [ 1913 Webster ]

1. To put poison upon or into; to infect with poison; as, to poison an arrow; to poison food or drink. “The ingredients of our poisoned chalice.” Shak. [ 1913 Webster ]

2. To injure or kill by poison; to administer poison to. [ 1913 Webster ]

If you poison us, do we not die ? Shak. [ 1913 Webster ]

3. To taint; to corrupt; to vitiate; as, vice poisons happiness; slander poisoned his mind. [ 1913 Webster ]

Whispering tongues can poison truth. Coleridge. [ 1913 Webster ]

v. i. To act as, or convey, a poison. [ 1913 Webster ]

Tooth that poisons if it bite. Shak. [ 1913 Webster ]

a. 1. Capable of poisoning; poisonous. [ Obs. ] “Poisonable heresies.” Tooker. [ 1913 Webster ]

2. Capable of being poisoned. [ 1913 Webster ]

. In Australia: (a) Any fabaceous shrub of the genus Gastrolobium, the herbage of which is poisonous to stock; also, any species of several related genera, as Oxylobium, Gompholobium, etc. (b) The plant Myoporum deserti, often distinguished as Ellangowan poison bush or dogwood poison bush. (c) The ulmaceous plant Trema cannabina, which, though not poisonous, is injurious to stock because of its large amount of fiber. [ Webster 1913 Suppl. ]

. 1. A cup containing poison. [ Webster 1913 Suppl. ]

2. A cup that was supposed to break on having poison put into it. [ Webster 1913 Suppl. ]

n. One who poisons. Shak. [ 1913 Webster ]

a. Having the qualities or effects of poison; venomous; baneful; corrupting; noxious. Shak. -- Poi"son*ous*ly, adv. -- Poi"son*ous*ness, n. [ 1913 Webster ]

a. Poisonous.[ Obs. ] Holland. [ 1913 Webster ]

n. [ See Poise. ] Weight. [ Obs. ] [ 1913 Webster ]

n. [ OE. porpeys, OF. porpeis, literally, hog fish, from L. porcus swine + piscis fish. See Pork, and Fish. ] 1. (Zool.) Any small cetacean of the genus Phocæna, especially Phocæna communis, or Phocæna phocæna, of Europe, and the closely allied American species (Phocæna Americana). The color is dusky or blackish above, paler beneath. They are closely allied to the dolphins, but have a shorter snout. Called also harbor porpoise, herring hag, puffing pig, and snuffer. [ 1913 Webster ]

2. (Zool.) A true dolphin (Delphinus); -- often so called by sailors. [ 1913 Webster ]

Skunk porpoise, or
Bay porpoise (Zool.), a North American porpoise (Lagenorhynchus acutus), larger than the common species, and with broad stripes of white and yellow on the sides. See Illustration in Appendix. [ 1913 Webster ]

v. t. To weigh, estimate, or rate below desert; to undervalue. [ R. ] Marston. [ 1913 Webster ]

a. 1. Not poised or balanced. [ 1913 Webster ]

2. Not poised or weighed; hence, regardless of consequences; unhesitating. [ Obs. ] Marston. [ 1913 Webster ]

v. t. [ 1st pref. un- + poison. ] To remove or expel poison from. [ Obs. ] South. [ 1913 Webster ]

A hydrometer. [ 1913 Webster ]