IonicPronunciation: /ʌɪˈɒnɪk/Definition of Ionic adjective 1relating to or denoting a classical order of architecture characterized by a column with scroll shapes (volutes) on either side of the capital. 2another term for Ionian. noun [mass noun] 1the Ionic order of architecture. 2the ancient Greek dialect used in Ionia. Origin: late 16th century: via Latin from Greek Iōnikos, from Iōnia (see Ionia)Ionic in other Oxford dictionaries Definition of Ionic in the US English dictionary