What does flaccid mean?
"Flaccid" describes anything that has lost its firmness: soft, limp, and hanging slack instead of holding a taut or vigorous shape. Its most literal applications are physical — muscles lacking tone, skin that has gone loose, plant leaves wilting for want of water — and it carries real weight in medicine and biology, where "flaccid paralysis" names the limp weakness characteristic of conditions such as polio. The word also works figuratively, and often damningly: a flaccid argument, speech, or response is one that lacks energy, conviction, or force. That flexibility makes it useful across registers, from clinical reports to literary criticism, though its bodily associations lend it a faintly unflattering edge when applied to people. Derived from Latin "flaccus" (limp or drooping), it entered English in the seventeenth century. A small pronunciation trap adds to its character: despite the double C in its spelling, the standard pronunciation is /ˈflæsɪd/ — the letters sound like "s," not "ks."
adjectiveSoft, limp, and lacking firmness or vigor; drooping rather than stiff or taut. Applied both to physical things (flesh, plant tissue) and, figuratively, to arguments, efforts, or leadership that lack energy and force.
- (of flesh, muscle, or body tissue) soft, loose, and lacking tone or firmness.
- (of plants or plant tissue) limp and drooping from loss of water or turgor pressure.
- (figurative) lacking vigor, force, or effectiveness — said of writing, arguments, leadership, or efforts.
"The weeks of drought left the garden's once-proud dahlias flaccid against the fence."
"After months without exercise, he noticed his arms had grown noticeably flaccid."
"Critics dismissed the senator's speech as a flaccid apology that satisfied no one."
"Flaccid" comes from the same Latin root as "flaccid" does in medicine — where "flaccid paralysis," the limp weakness caused by polio, is its most feared legacy.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of flaccid
"Flaccid" derives from the Latin adjective "flaccidus," meaning limp or drooping, formed from "flaccus," an epithet describing hanging looseness (the Roman poet Horace was nicknamed after it). The word passed into English in the early seventeenth century, likely via French influence, retaining both its literal sense of bodily limpness and its figurative sense of feebleness. It shares its root with the noun "flaccidity" and stands alongside other Latin-descended words denoting slackness rather than stiffness.
Related word forms
How flaccid is actually used
Register is neutral-to-formal; the word appears freely in medical and scientific writing as well as everyday prose. Because it is strongly associated with limpness of flesh, using it about a person's body can carry an unflattering, even mocking connotation — choose it deliberately. In British English a variant pronunciation with /ks/ is traditional, though /s/ is now standard on both sides of the Atlantic; note also that "flaccid" is one of relatively few words whose spelling is widely mispronounced (the double C is pronounced /s/, not /ks/).
Easily confused with flaccid
Spastic (or spastic paralysis) refers to muscles that are stiff and rigid with uncontrolled contraction, whereas flaccid refers to muscles that are soft and lacking tone.