Obdiplostemonous (a.)
definition: Having twice as many stamens as petals
Those of the outer set being opposite the petals; -- said of flowers.
Obdiplostemonous is a 16 letter word that begins with an O and ends in an S

Ophthalmological (a.)
definition: Of or pertaining to ophthalmology.

Ophthalmological is a 16 letter word that begins with an O and ends in an L

Opisthopulmonate (a.)
definition: Having the pulmonary sac situated posteriorly; -- said of certain air-breathing Mollusca.

Opisthopulmonate is a 16 letter word that begins with an O and ends in an E

Oppositipetalous (a.)
definition: Placed in front of a petal.

Oppositipetalous is a 16 letter word that begins with an O and ends in an S

Oppositisepalous (a.)
definition: Placed in front of a sepal.

Oppositisepalous is a 16 letter word that begins with an O and ends in an S

Orbitosphenoidal (a.)
definition: Of or pertaining to the orbitosphenoid bone; orbitosphenoid.

Orbitosphenoidal is a 16 letter word that begins with an O and ends in an L

Ornithoidichnite (n.)
definition: A fossil track resembling that of a bird.

Ornithoidichnite is a 16 letter word that begins with an O and ends in an E

Orthographically (ad)
definition: according to orthographic projection.

Orthographically is a 16 letter word that begins with an O and ends in a Y

Orthographically (ad)
definition: according to the rules of proper spelling

Orthographically is a 16 letter word that begins with an O and ends in a Y

Orthographically (ad)
definition: In an orthographical manner

Orthographically is a 16 letter word that begins with an O and ends in a Y

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