Comment: The nominal stem *jis,*jis:a- (cf. also Tab. Düb. jizi, Ag. Bursh. is:) means "year"; its adjectival derivate (often in suffixed form: *jis:V-rV-, sometimes metathesized as is usual with adjectives) means "old" which is a common semantic shift (cf. also external evidence).
See Лексика 1971, 182; Хайдаков 1973, 110; Талибов 1980, 314.
