Female and male first names beginning with the letter “O”..

Onni is a Finnish name meaning 'happiness', originating from the Finnish word 'onninen'.

Onnie is a unique and charming Dutch name that serves as a diminutive form of Agnes or Anna, with meanings ranging from 'lamb' to 'grace,' and originating from Latin and Hebrew roots respectively.

Onnix is a rare, unique name of unknown origin and meaning.

Onofre is a rare Spanish given name derived from the Basque town 'Oñati', associated with Saint Onofre, known for his faith and endurance.

Onofrio is an Italian male given name of Byzantine origin, derived from Greek elements meaning "towards light" or "bringer of light." It is associated with Saint Onofrio, an Egyptian hermit venerated as a saint by both Eastern Orthodox and Roman Catholic churches.

Onorio is a Latin-derived male name meaning 'honor' or 'respect', reflecting its bearer's high regard in ancient Roman society.

Onslow is an uncommon English given name derived from Old English words meaning "lamb" and "woodland clearing," signifying "meadow where lambs graze." It has a rich historical background dating back to medieval England, with notable figures like Sir Arthur Onslow bearing the name.

Ontario is an Iroquoian origin name meaning "beautiful lake" or "shining land", first applied to Lake Ontario in Canada.

Ontarius is an African American created male given name from the early 20th century, with uncertain etymology but sometimes associated with being outstanding.

Onterio: A rare, distinct Native American (Oneida) name meaning 'east', traditionally given to those born at dawn and believed destined for greatness.

Onterrio is a unique and distinctive name with unknown origins, possibly invented or of African descent, but its exact meaning remains unclear despite its rare usage throughout history.

Antonio is an Italian male given name derived from Latin 'antonius', meaning 'priceless' or 'invaluable'.

Ontrell is an unusual African American given name created in recent decades, with no documented meaning or history but often associated with power or strength.

Onur is a Turkish male name meaning "honor" or "respect," reflecting highly valued qualities in Turkish culture.

Onyedikachi is an Igbo name from Nigeria, meaning 'God has heard goodness'.

Onyekachi is an Igbo name, originating from Nigeria, which combines "person" (Onye) and "God has made great" (Kachi), signifying parental hopes for their child's success.

Onyekachukwu is an Igbo Nigerian male name meaning "God has done something great.

Onyx is a captivating unisex name of Greek origin, derived from the word "onyx" meaning nail or claw. In ancient mythology, Onyx was a giant turned into a stone, symbolizing strength, courage, and protection across various cultures. While historically used sparingly, Onyx has gained popularity as a unique, powerful choice for parents seeking a meaningful name with deep roots in tradition.

Onyxx is a rare, unisex name of Latin origin, derived from the precious stone onyx, symbolizing strength and beauty.