interesting

(verb) excite the curiosity of; engage the interest of. Synonyms: interest.

(verb) be on the mind of. Synonyms: concern, interest, occupy, worry. Example: "I worry about the second germanic consonant shift."

(verb) be of importance or consequence. Synonyms: matter to, interest. Example: "This matters to me!."

(adj) arousing or holding the attention. Synonyms: interesting (vs. uninteresting).