• Oo

    Origin 1

    Representation of a long-o sound.

    Full definition of oo

    Noun

    oo

    (plural oos)
    1. (obsolete) The Greek letter omega.

    Pronunciation

    Origin 2

    From Hawaiian ‘ō‘ō

    Noun

    oo

    (plural oos)
    1. A Hawaiian honeyeater of the genus Moho, now believed to be extinct.----
    © Wiktionary