1. The act of intruding; encroachment; the penetrating of rock, while in a melted state, through or among other rocks.

Nuttall's Standard dictionary of the English language By Nuttall, P.Austin

• intuision,
• intrueision,
• intruction,
• intution,
• intiution,
• intrustion,
• instrution,
• intrutions,
• intrussion,
• intesion,
• intrusing,
• intursion,
• instrucion,
• instrusion,
• instrustion,
• inpresion,
• intruption,
• intrudtion,
• interusion,
• intrution

• indris,
• intuition,
• intransigent,
• intrinsic,
• intrude on,
• introitus,
• intruding,
• in terms of,
• intrusive,
• introversion,
• intrinsical,
• intron,
• intrude,
• intromission,
• in turn,
• intrust.

The adverb form of "intrusion" is "intrusively".

The adjective form of the word "intrusion" is "intrusive".

The plural of the "intrusion" can be the "intrusions".

The singular of the "intrusion" can be the "intrusion".