intrusive implies a tactless or otherwise objectionable thrusting into others' affairs. Intrusive rock is formed when hot liquid rock cools and becomes solid inside the earth's crust (= outer layer). Granite is an intrusive igneous rock, that is formed from magma underground. The thickness of … Define intrusive. intrusive synonyms, intrusive pronunciation, intrusive translation, English dictionary definition of intrusive. Intruding or tending to intrude. Definition of intrusive adjective from the Oxford Advanced Learner's Dictionary. too direct, easy to notice, etc. in a way that is annoying or upsetting. The constant presence of the media was very intrusive. Something that is intrusive disturbs your mood or your life in a way you do not like. The cameras were not an intrusive presence. Staff are courteous but never intrusive. annoying, bothersome, interfering, distracting, irksome, worrisome, troublesome, irritating, disturbing. an act or instance of intruding: [uncountable] She hated the intrusion into her … Factsheet What does the word intrusive mean?