noun

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

adjective

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. Of rocks: forced, while in a plastic or molten state, into the cavities or between the cracks or layers of other rocks.

Synonyms: disturbing, interrupting, uninvited, unwelcome