noun
The sweet flag, Acorus calamus.
(ornithology) A quill; the hard, horny, hollow, and more or less transparent part of the stem or scape of a feather.
A fish of genus Calamus in family Sparidae; certain porgies.
A palm in genus Calamus, of rattan palms.
(botany) A fistular stem without an articulation.
(Christianity, historical) Synonym of fistula (“tube for sucking Eucharist wine”).