A quill; the hard, horny, hollow, and more or less transparent part of the stem or scape of a feather.
Synonym of fistula (“tube for sucking Eucharist wine”)
A palm in genus Calamus, of rattan palms.
The sweet flag, Acorus calamus.
A fish of genus Calamus in family Sparidae; certain porgies.
Synonym of plumule (“the first bud, or growing point, of a plant embryo, situated above the cotyledons”)
In the obsolete theory of pangenesis propounded by the English scientist Charles Darwin (1809–1882): a hypothetical particle once thought to be the basis of heredity.
Synonym of dendritic spine (“a small membranous protrusion from the dendrite of a neuron that typically receives input from a single axon at the synapse”)