a simple embryonic leaf in seed-bearing plants, which, in some species, forms the first green leaf after germination
2.
a tuft of villi on the mammalian placenta
Derived forms
cotyledonal (ˌcotyˈledonal)
adjective
cotyledonary (ˌcotyˈledonary)
adjective
cotyledonous (ˌcotyˈledonous) or cotyledonoid (ˌcotyˈledoˌnoid)
adjective
Word origin
C16: from Latin: a plant, navelwort, from Greek kotulēdōn, from kotulē cup, hollow
cotyledon in American English
(ˌkɑtəˈlidən)
noun
the first single leaf or one of the first pair of leaves produced by the embryo of a flowering plant, or any of various similar structures found in conifers
see also monocotyledon, dicotyledon
Derived forms
cotyledonous (ˌcotyˈledonous)
adjective or ˌcotyˈledonal
Word origin
ModL < L, name of a plant < Gr kotylēdōn < kotylē, a hollow, cavity