AO adjective 1noun 7forms 1 adjective1 •Initialism of adults only. noun7 •Initialism of atomic orbital. •Abbreviation of area of operations. •Abbreviation of autonomous oblast. •Abbreviation of autonomous okrug. •(Hong-Kong) Initialism of administrative officer. •Abbreviation of alpha and omega. •(US, Navy) Abbreviation of auxiliary oiler. formsAOs
