Stimulant

Part of speech: noun

Pronunciation: /ˈstɪmjʊlənt/

Definitions

1. A substance that increases activity, alertness, or energy levels in the body or mind
2. A chemical agent that promotes heightened alertness, increases physical performance, and stimulates mental activity
3. A compound that boosts bodily or cognitive energy or alertness ; an object or event that triggers or amplifies a reaction or response

Etymology: The Latin "stimulus" was a goad, the pointed stick used to prod oxen and other draft animals forward. Its literal sense was the sting that spurs an animal into motion, and the figurative sense of a spur to action came later. English took the idea from Latin, and "stimulant" comes from the present participle of the related Latin verb "stimulare," meaning "to goad." The sense of a substance that energizes the body grew out of that figurative meaning. A stimulant prods the nervous system into greater activity, much as a goad prods an ox. Today the term covers everything from caffeine in coffee to prescription drugs for attention disorders, though the physical image of the goad has largely faded from view.

Synonyms: energizer, invigorator, catalyst

Antonyms: sedative, depressant