To engage the attention of; to awaken interest in; to excite emotion or passion in, in behalf of a person or thing.
Action films don't really interest me.
To be concerned with or engaged in; to affect; to concern; to excite.
To cause or permit to share.
Having or showing interest.
I'm very interested in going to see that play.
Motivated by considerations of self-interest; self-serving.
Owning a share of a company.