24 of the Best Synonyms and Antonyms for ‘Zealous’


By Dr Oliver Tearle

The word ‘zealous’ is used to describe someone who has zeal: a passionate enthusiasm for, or devotion to, a particular cause, idea, or objective. Curiously, there is an etymological link between the similar words zealous and jealous: zealous is derived from zeal, of course, and that word is ultimately from the Latin meaning ‘jealousy, rivalry, or emulation’. Since someone might be described as jealously guarding something they support with zeal, one can see the link.

But what are some other related words which might serve as synonyms for ‘zealous’? Here are the best alternative terms, along with some information about their meanings and origins.


Synonyms for the word ‘zealous’

One of the best-known and most commonly used synonyms for zealous is found up at the other end of the alphabet: ARDENT, which is from the Latin for ‘burn’. And indeed, BURNING is another adjective that can serve as an alternative to zealous: some writers even talk about the ‘burning zeal’ of someone who is ardently devoted to their cause, whether religious, political, or even artistic. This ‘burning’ motif is also present, more obviously, in a synonym like FIERY.

A word used virtually synonymously with ardent is FERVENT, which, like ‘ardent’, originally meant simply ‘burning’ or ‘fiery’. As the OED records, fervent is from the Latin for ‘boil’ or ‘glow’, so its etymology is similarly bound up with ideas of heat, and this became translated into the figurative meaning of glowing with ardent desire or passion for something. A related adjective is FERVID, from the same Latin root, though fervid only entered the English language in the late sixteenth century, several centuries after fervent.

ENTHUSIASTIC, meanwhile, can serve as a good word for ‘zealous’ because it originally had a much stronger meaning than it now possesses: whereas it’s often used in quite a general and mild way now to describe someone who is KEEN on something, enthusiasm is actually from the ancient Greek for ‘frenzy’ or ‘inspiration’, and originally described someone who was possessed or inspired by a god.

FANATICAL has a religious flavour to it, though it can be used about non-religious subjects (and people) as well. However, there’s no denying that its etymology is bound up with worship, as it’s from the Latin fānum meaning ‘temple’; indeed, to this day a ‘fane’ is another (poetic) word for a temple, as in Keats’s ‘Ode to Psyche’: ‘Yes, I will be thy priest, and build a fane / In some untrodden region of my mind’.

Again, as with enthusiasm, fanatical initially meant ‘frenzied’ or ‘possessed by the spirit of a god or goddess’ (or a demon, for that matter). The word fanatical, when used about somebody’s enthusiasm, is often used in a judgmental manner to suggest that their zeal is misplaced or mistaken.

Meanwhile, PASSIONATE is a word which also has origins in religious literature, and it has a somewhat surprising etymology: it’s from the Latin for ‘suffering’ or ‘torment’ and is often used (with a capital P) to refer to the suffering undergone by Jesus Christ during the Crucifixion (hence ‘The Passion of the Christ’). It’s etymologically related to patient, the idea being that if you’re waiting for something you are ‘suffering’ to wait for it.

But if you wish to emphasise the fact that someone is loyal to a particular cause or idea, then COMMITTED is a good word to convey their zealotry, as is DEVOTED, both of which have very similar meanings.

Related to the words intend and intention, and so also conveying the idea of commitment to a cause or objective, is the adjective INTENSE. Someone’s fervour for a particular ideal or goal might be described as an intense fervour. It’s ultimately from the Latin for ‘stretch’, as in tension.

VEHEMENT is etymologically related to another v-word: violent. It’s from a Latin word meaning ‘possessing great or violent force’. Although in the Middle Ages it originally referred to pain or illness (or things like intense heat or cold – or a vehement wind, for instance), by the late fifteenth century it had also come to mean ‘strong, intense, fervent’.

Another v-word worth knowing about in this connection is VIGOROUS. It was first applied to physical strength or force, but is sometimes used now about the strength of feeling someone has for (or about) something.

Let’s conclude this synonyms list with a couple beginning with E: EAGER and ENERGETIC. Both are less strong than many of the other words on this list, but they can also serve as fairly good alternative words to convey the idea of zeal or passionate commitment.


Antonyms for the word ‘zealous’

Since zeal is a passionate and enthusiastic commitment to something, common antonyms for zealous include APATHETIC or INDIFFERENT, conveying that one is UNCARING about the outcome of something. Indeed, if to be zealous is to be enthusiastic, to be the opposite is to be UNENTHUSIASTIC.

COOL, COLD, DISPASSIONATE, and IMPASSIVE all suggest that one is unmoved by a particular topic or belief. It’s hardly surprising that, since burning and fiery both convey the idea of zeal, ‘cold’ words should be used to reflect the opposite.