intrusive

Etymology

Back-formation from intrusion, + -ive.

adj

1. Tending to intrude; doing that which is not welcome; interrupting or disturbing; entering without permission or welcome.
   Did it ever cross your mind that he might find all those questions you ask intrusive?
2. (geology) Of rocks: forced, while in a plastic or molten state, into the cavities or between the cracks or layers of other rocks.
3. (linguistics) epenthetic

noun

1. (geology) An igneous rock that is forced, while molten, into cracks or between other layers of rock