| form genus | (n) (biology) an artificial taxonomic category for organisms of which the true relationships are obscure |
| form genus | (n) an artificial taxonomic category established on the basis of morphological resemblance for organisms of obscure true relationships especially fossil forms |
| genus rhizoctinia | (n) form genus of imperfect fungi some species of which are now placed in genera Pellicularia and Corticium because their perfect stages have been found, Syn. form genus Rhizoctinia |