- soft and limp; not firm; flabby: flaccid biceps.
- lacking force; weak: flaccid prose.
- lacking firmness; soft and limp; flabby
1610s, from French flaccide or directly from Latin flaccidus “flabby,” from flaccus “flabby, flap-eared,” of uncertain origin (OED suggests it’s imitative). Related: Flaccidly; flaccidity.
- Lacking firmness, resilience, or muscle tone.