Alternative spelling of addition polymerization

(chemistry) A form of polymerization in which copies of a monomer are repeatedly added to one end of an existing polymer

(mathematics) A unary function that preserves the addition operation; a unary function f such that for any x and y: f(x + y) = f(x) + f(y).

(music) The practice of enlarging and revising the orchestration of an earlier work, usually a Baroque piece, to accommodate the larger contemporary orchestras and tastes of the time.

(grammar) A form of plural in which the referent is a collection of those items to which the stem itself refers (within a given frame of reference).

(sports) stoppage time

plural of additive plural

(mathematics) A subbranch of combinatorics that concerns additive problems expressed using sumsets.

3D printing.

(number theory) The subfield of number theory concerning the behaviour of sumsets (integer sets added to each other elementwise).