ARIL'LUS, noun The exterior coat or covering of a seed, fixed to it at the base only, investing it wholly or partially, and falling off spontaneously; by some writers called, from the Greek, Calyptra. It is either succulent, or cartilaginous; colored, elastic, rough or knotted.
Source: Webster's 1828 American Dictionary ↗ · public-domain · returned verbatim, no AI