ODETTA:  see Odette.

ODETTE:  Feminine diminutive of Old French name Oda, itself related to Otto, "prosperity."

OLAVE:  see Olive.

OLGA:  Russian feminine form of Oleg, "holy," and equivalent of Scandinavian Helga, "holy."  No regular variants.

OLIVE:  From the plant, itself implying "peace" through its olive branch.  Variant, Olave, exists.  Diminutive is Olivette.

OLIVETTE:  see Olive.

OLIVIA:  From Latin or  Italian oliva, "olive."  Also feminine equivalent of Oliver, "olive tree."

OLWEN:  Welsh name meaning "white footprints."

ONA:  Probably an alteration of Oona, "together."

OONA:  English form of Irish name Una, "together."  Variant, Oonagh, exists.

OONAGH:  see Oona.

OPAL:  From the precious stone.

OPHELIA:  Apparently feminine of Greek Ophelos, "profit; help."

OPRAH:  Variant of biblical name Orpah, "she who turns her back."

ORIANA:  Latin name meaning "dawn" or "sunrise.".

ORINTHIA:  Greek name meaning "to excite" or "to stir the mind."

OTTOLINE:  Diminutive of French or German Ottilie, itself from medieval name Odila, the feminine form of Otto, "prosperity."