Other forms: tepidest
Tepid means lukewarm or half-hearted. If the applause for your mime-on-a-unicycle performance was more tepid than enthusiastic, it might be time to find a new hobby.
Around the year 1400, the word tepid evolved from the Latin tepidus, an adjective meaning “lukewarm,” which itself is derived from the Latin tepere, a verb meaning “to be warm.” Tepid people or things are lukewarm or lacking in enthusiasm or emotion. Bathwater that’s been sitting in the tub for two hours is probably tepid. So is the greeting you might give to a former friend you run into at the movie theater.