adjective

zealous

ZEL-us/ˈzeləs/

Showing strong enthusiasm or devotion.

The zealous volunteer keeps collecting litter after filling several bags.

An enthusiastic volunteer throws herself into a litter cleanup, leaning eagerly toward another discarded bottle with her grabber despite already having filled several collection bags.

Etymology

Latin “full of zeal” underlies both zealous and jealous. Zealous emphasizes fervent commitment to a person or cause, while jealous developed the familiar sense of possessive suspicion.

In context

Allellu67:38

knows the eagerness with which men propagate all singular opinions, and the delight which attends their favourable reception. None are more zealous than the apostles of infidelity and atheism.

Proofs of a Conspiracy [Part 1 of 2] by John Robison | Full Audiobook, Read-Along

More examples

He became a zealous supporter of the campaign.
Her zealous attention improved every detail.
The committee welcomed their zealous participation.

Forms

zealous · more zealous · most zealous

zeal noun — strong enthusiasm or devotion

Similar words

enthusiastic: Enthusiastic is the general term; zealous emphasizes devoted, energetic commitment.
devoted: Devoted stresses loyalty; zealous adds active enthusiasm.