ARDICA. – The term is used particularly in Ravenna to denote the portico of a church, which is a reduced form of the atrium, as, for example, the atrium in front of the basilica of S. Croce founded by Galla Placidia and in S. Vitale. The word itself should be merely the Latinized form of the Greek νάξαθης, “natrice” [water-snake], since both words signify the same thing.
Bibl.: Agnello, *Liber Pontificalis ecclesiae Ravennae*, ed. Holder-Egger, in *MGH, Scriptores rerum Langobardicarum*, pp. 209, 4; 204, 1; 330, 13; 18; 341, 38; 344, 39; 346, 34; 348, 32; 352, 21; 31; 360, 16; 373, 28, passages used by P. Verzone, *I monumenti dell'alto Medioevo nell'Italia settentrionale*, Milano 1943.