(arithmetic) An empty sum.

A relatively large single payment of money often paid and received instead of, or in addition to, a sequence of smaller payments.

(arithmetic) The result of adding no numbers, conventionally defined to equal zero.

(insurance) The amount of benefit that an insurance contract pays out to a beneficiary on the occurrence of a contingent insured event.

(linear algebra) A linear subspace which is the linear span of the union of two subspaces (of some vector space).

(mathematics, of a positive integer) The sum of all digits.

Alternative form of sum of its parts / Used other than figuratively or idiomatically: see sum, of, parts.

A Chinese vegetable, a variety of Brassica rapa parachinensis subspecies, similar to bok choy but slimmer, with smooth green leaves and pale green stems, and clusters of flowers on the tips of the inner shoots

(game theory) Pertaining to a game or situation where overall benefits to all participants can increase.

(topology) A one-point union of a family of topological spaces.