(mathematics) A theorem in the elementary theory of numbers: let a and b be integers, not both zero, and let d be their greatest common divisor. Then there exist integers x and y such that ax + by = d.

(medicine) calcification of ligaments near their attachment points to the spine

(mathematics) A certain kind of subset of a partially ordered set.

Alternative form of nonidiomatic (preferred in British English)

(genetics) Of corresponding segments of a chromosome in different individuals, identical because they were inherited from a common ancestor without crossover.

Alternative form of matinée idol

plural of personal identification number

(logic) The logical principle that anything equals itself, expressed by the symbolic equation A=A.

Synonym of body integrity identity disorder

(psychology) A psychological disorder characterized by the desire to have one or more healthy limbs amputated.