An outgrowth or enlargement, especially an abnormal one, such as a wart.
A usually unwanted or unnecessary accretion: "Independent agencies were an excrescence on the Constitution"(Los Angeles Times).
[Middle English, from Latin excrēscentia, from neuter pl. of excrēscēns, excrēscent-, present participle of excrēscere, to grow out : ex-, ex- + crēscere, to grow; see ker-2 in Indo-European roots.]
1533, from L. excrescentia (pl.) "abnormal growths," from excrescentem (nom. excrescens), prp. of excrescere "grow out," from ex- "out" + crescere "to grow" (see crescent).
Main Entry: ex·cres·cence Pronunciation: ik-'skres-&n(t)s Function: noun : an outgrowth or enlargement: as a: a natural and normal appendage or development excrescence from the scalp> b: an abnormal outgrowth excrescences in the colon> —ex·cres·cent/ik-'skres-&nt/adjective