t, [from gjósa, q. v., and different to geisa]:—to rush furiously, gush, = Lat. grassari, of fire, the sea, etc.; hann lætr g. eld ok járn, Fms. xi. 42:—usually dep., geysask vötn at þeim með forsfalli, Ó. H. 164; þá geysisk hafit á löndin, Edda 41; geystisk at því allr lands-múgr, Ó. H. 34; múgrinn flotans geystisk inn á stórskipin, Fms. viii. 227: part. geystr, gushing, rushing forth, Nj. 247, Fms. vii. 326, Fb. i. 253: metaph. enraged, Fms. vii. 230, viii. 202, Hkr. ii. 356: big, enormous, Fms. vii. 99:—neut. geyst, as adv. furiously, violently, i. 165, Finnb. 352.