• WordNet 3.6
    • adj pentamerous divided into five parts; specifically, having each floral whorl consist of five (or a multiple of five) members "pentamerous flowers"
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Webster's Revised Unabridged Dictionary
    • Pentamerous (Zoöl) Belonging to the Pentamera.
    • Pentamerous (Biol) Divided into, or consisting of, five parts; also, arranged in sets, with five parts in each set, as a flower with five sepals, five petals, five, or twice five, stamens, and five pistils.
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Century Dictionary and Cyclopedia
    • pentamerous Five-parted; five-jointed; composed or consisting of five parts or five sets of similar parts. Specifically – In entomology: Five-jointed, as a beetle's tarsus.
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Chambers's Twentieth Century Dictionary
    • adj Pentamerous pen-tam′ėr-us (bot.) consisting of or divided into five parts
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Webster's Revised Unabridged Dictionary
Penta-, + Gr. part
Chambers's Twentieth Century Dictionary
Gr. pente, five, meros, part.


In literature:

Pentamerous: species having five-jointed tarsi.
"Explanation of Terms Used in Entomology" by John. B. Smith
To take an example, the group Pseudostrobus, characterized by pentamerous leaf-fascicles, appears in many systems.
"The Genus Pinus" by George Russell Shaw
It is pentamerous, complete, symmetrical and regular.
"Encyclopaedia Britannica, 11th Edition, Volume 10, Slice 5" by Various