Lewis Short
(adverb) : cessim (cossim), cesso; cf. coxim
* Bending or turning in; hence, also, turned backwards, backwards (mostly anteand post-class.): cum domum ab Ilio cessim revertero, Varr. ap. Non. p. 247, 26; p. 276, 9: cessim ire,Dig. 9, 2, 52, ยง 2; Just. 2, 12, 7: lagena orificio cessim (obliquely) dehiscente patescens, App. M. 2, p. 121, 8.
Charlton T. Lewis, Charles Short, A Latin Dictionary