COMMUNICATIONS RETINAL CYSTS ANDRETINOSCHISIS* BY C. G. KEITH DepartmentofPathology, Institute ofOphthalmology, University ofLondon SINCE the term retinoschisis came into commonophthalmological parlance, it has oftenbeenusedas thoughthe conditionwereadefinite entity, differing fromretinal cysts bythe process byWhichit arose.
The definition of imperative is something that has authority or is absolutely necessary. 1  An example of imperative is the power that a government has over its people.  An example of imperative is the decision to give a cesarean in a breach birth.
Wiktionary (0.00 / 0 votes) Rate this definition: imperative (Noun). The grammatical mood expressing an order (see jussive). In English, the imperative form of a verb is the same as that of the bare infinitive. The verbs in sentences like Do it! and Say what you like! are in the imperative. imperative (Noun).