1. hostificus — de Vaan
hostificus 'hostile' (Acc.+). Pit. *xosti-. ; PIE *ghosti- 'stranger, guest*. IE cognates: OCS gostb, Ru. gost\ SCr. gost> gen. gosta, Go. gasts, OHG gast, OIc, gestr 'guest'. In theory, 'guest' could be derived from the root *g(y)hes- (in that case, rather *ghes-) 'to eat, devour' of Skt. ghas-. Yet a suffix -//- does not normally indicate an agent noun, nor is o-grade common in this type of derivative. Heidermanns … — [de Vaan, s.v. hostificus, p. 305]