What does cannonball mean?
A cannonball is a large, solid, usually spherical projectile — historically made of iron or stone — designed to be fired from a cannon. Once a central element of siege warfare and naval battles from roughly the fourteenth through nineteenth centuries, the term survives today largely in military history, museums, and figurative language. The word has also taken on a playful modern life: to 'do a cannonball' means to leap into water with the knees hugged to the chest so the body lands as a rounded mass, producing a dramatic splash. This informal, chiefly American sense shows how a weapon's name can migrate into everyday recreation. Whether describing an artifact of artillery or a splashy dive, 'cannonball' carries vivid connotations of force, weight, and impact.
A solid round projectile, traditionally of iron or stone, fired from a cannon.
"Archaeologists unearthed several cannonballs near the ruins of the coastal fort."
Often used in plural when referring to battlefield finds.
(Informal) To dive or jump into water with the knees drawn up to the chest, landing in a rounded position that makes a large splash.
"The kids took turns cannonballing off the dock."
Chiefly North American colloquial usage.
Regular plural; standard in both British and American English.
"The shipwreck yielded dozens of corroded cannonballs."
The classic poolside 'cannonball' dive is named after the way the body curls into a compact sphere — exactly like the ammunition it imitates.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of cannonball
Cannonball is a compound of 'cannon', which entered English in the late Middle Ages likely via Old French from Italian 'cannone' (large tube), ultimately related to Latin 'canna' meaning reed or tube, combined with 'ball', from Old Norse 'böllr' or Old English. The compound arose once cannons themselves became common in European warfare, probably in the sixteenth century. Its cognates therefore include other words built on the same tube-root lineage, such as 'cannonade' and 'cannoneer'.
How cannonball is actually used
The projectile sense is neutral and historical/military in register. The diving sense is distinctly informal and colloquial, especially North American, and is often used with verbs like 'do' or 'pull'.
Easily confused with cannonball
A canon is an official rule, list, or body of works (or a clergyman), whereas a cannonball is a projectile fired from a cannon — the two differ by one letter and in meaning entirely.