a. Serving or tending to concentrate; characterized by concentration. [ 1913 Webster ]

A discrimination is only possible by a concentrative act, or act of attention. Sir W. Hamilton. [ 1913 Webster ]

n. 1. The quality of concentrating. [ 1913 Webster ]

2. (Phren.) The faculty or propensity which has to do with concentrating the intellectual the intellectual powers. Combe. [ 1913 Webster ]