What does bonk mean?
Bonk is an informal English word meaning to strike or bump something, usually with a light, often accidental force — most commonly a knock on the head, as when someone 'bonks' their skull on a low ceiling or open cupboard door. It functions both as a verb and as a noun for the blow itself, and its sound gives it a playful, comic quality that keeps it firmly in casual rather than formal usage. In British and Australian slang it carries a separate, vulgar sense referring to sexual intercourse. Among cyclists, 'bonking' has yet another specialized meaning: the sudden collapse in energy that occurs when the body's glycogen stores run out mid-ride, equivalent to runners' phrase 'hitting the wall.' Despite these varied senses, the core image remains the same — a blunt, unglamorous impact. The word's onomatopoeic feel makes it memorable and widely understood across the English-speaking world.
To hit or bump someone or something, typically lightly and often accidentally, especially on the head.
"She stood up too fast and bonked her head on the shelf above."
Chiefly informal; often used humorously about minor self-inflicted knocks.
A light blow or bump, especially one delivered to the head.
"He gave his little brother a playful bonk on the head with a rolled-up newspaper."
Regular pluralization applies only to the noun form.
"The comedy sketch featured a series of well-timed bonks with a rubber mallet."
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of bonk
Bonk appears to be a 20th-century word of uncertain origin, likely imitative in nature — echoing the dull thud of a light blow. It emerged first in British English in the early decades of the century, initially as a noun for a knock on the head before developing verbal use. Its later senses (sexual slang and the cycling 'hit the wall') arose independently in the latter half of the 20th century. No established cognates exist in other languages.
Related word forms
How bonk is actually used
Informal register throughout; the cycling sense of 'bonk' refers to sudden exhaustion from depleted glycogen (hitting the wall). The sexual sense is chiefly British/Australian vulgar slang.
Easily confused with bonk
'Conk' means to hit on the head or (of an engine/machine) fail suddenly, while 'bonk' is specifically an informal term for a bump or blow, often to the head.