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.
N.B.: Nota Bene. The Latin imperative means Take notice of this very carefully, that is, pay special attention to this part because it is unusually important, tricky, or confusing. Usage: All assignments are due at the beginning of class.