Definition of: intrusive

(in·tr′siv) adj
1. Coming without warrant; intruding; obtrusive; prone to intrude.
2. Geol. Formed by solidification before reaching the surface of the earth, as certain igneous rocks; plutonic.
3. Phonet. Referring to speech sounds in a word which do not have etymological basis, but result from the adjustment of the vocal organs to the sounds preceding and following, as the d in spindle (Old English spinel).
—intrusive r An r sound sometimes heard between a word ending in a vowel and a following word beginning with a vowel, as in lawr office. [<L intrusus, pp. of intrudere. See INTRUDE.]
—in·tru′sive·ly adverb
—in·tru′sive·ness noun