(medicine) Any of the many genetic disorders due to an aspect of the body's immune system being either absent or failing to function normally.

(mathematics, number theory) For a given modulus n, a number g such that for every a coprime to n there exists an integer k such that gᵏ ≡ a (mod n); a generator (or primitive element) of the multiplicative group, modulo n, of integers relatively prime to n.

(religion) The representative leader of all Benedictine congregations.

plural of abbot primate

(number theory) A prime number which is one less than a power of two (i.e., is expressible in the form 2ⁿ-1; for example, 31=2⁵-1).

(number theory) A Fermat number that is prime.

(pharmacology) An anxiolytic drug.

Chinese primrose; Primula sinensis.

simple past tense and past participle of primary

(law) A person who is considered by the law enforcement agency investigating a crime to be the most likely suspect.