American Heritage® Dictionary of the English Language, Fourth
Edition - adj. Dropping off or shedding at an early stage of
development, as the gills of most amphibians or the sepals or
stipules of certain plants. Century Dictionary and Cyclopedia -
Having a tendency to fall or decay. specifically— In zoōl.,
falling off; dropping a way or shedding; deciduous, as the gills
of most amphibians, the milk-teeth of most mammals, the antlers
of deer, etc.: synonymous with deciduous, but implying an
earlier or speedler falling off. - adj. biology Of a part of an
organism, disappearing in the normal course of development. -
adj. botany Tending to fall early. GNU Webster's 1913 - (Bot. &
Zoöl.) Dropping off or disappearing early, as the calyx of a
poppy, or the gills of a tadpole. - adj. shed at an early stage
of development - Latin cadūcus ("falling; transitory").
(Wiktionary) - From Latin cadūcus, falling, from cadere, to
fall; see kad- in Indo-European roots. (American Heritage®
Dictionary of the English Language, Fo