sub·brach·i·al \|səb|brakēəl\adjective alsosub·brach·i·an\-ēən\ Etymology:subbrachial from New Latin subbrachialis, from Latin sub- + brachialis brachial; subbrachian from New Latin Subbrachiales + English -an — more at brachial : located beneath or nearly beneath a pectoral fin < ventral fins subbrachial >