Omphalomesenteric (a.)
definition: Of or pertaining to the umbilicus and mesentery; omphalomesaraic; as
The omphalomesenteric arteries and veins of a fetus.
Omphalomesenteric is a 17 letter word that begins with an O and ends in a C

Opisthobranchiata (n.)
definition: A division of gastropod Mollusca
In which the breathing organs are usually situated behind the heart. It includes the tectibranchs and nudibranchs.
Opisthobranchiata is a 17 letter word that begins with an O and ends in an A

Opisthobranchiate (a.)
definition: Of or pertaining to the Opisthobranchiata.

Opisthobranchiate is a 17 letter word that begins with an O and ends in an E

Opisthobranchiate (n.)
definition: One of the Opisthobranchiata.

Opisthobranchiate is a 17 letter word that begins with an O and ends in an E

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