[?k'spli:t?v, ?k-]
¦ noun
1. an oath or swear word.
2. Grammar a word or phrase used to fill out a sentence or a line of verse without adding to the sense.
¦ adjective Grammar (of a word or phrase) serving to fill out a sentence or line of verse.
Origin
ME (as adjective): from late L. expletivus, from explere 'fill out'.