The boundary of a convex set is always a convex curve. The intersection of all convex sets containing a given subset A of Euclidean space is called the convex hull of A. It is the smallest convex set containing A.
Rector (ecclesiastical) A rector is, in an ecclesiastical sense, a cleric who functions as an administrative leader in some Christian denominations, and in Islam. In contrast, a vicar is also a cleric but functions as an assistant and representative of an administrative leader.
A specialist who knows everything about something and nothing about anything else. The Devil's Dictionary Ambrose Bierce He leaves it to the specialist, which is as if he should leave his dinner to be eaten by a steam-engine.