The correspondences between PEC and PWC are quite satisfactory, both phonetically and semantically. The non-palatalized second *c: in PWC is due to assimilation (in a reduplicated stem; otherwise we would rather expect *c:āʒ́V). See Trubetzkoy 1930, 276 (with a probably wrong WC etymology, see under *ʔăjʒăɫʔV), Abdokov 1983, 113 (basically correct, but with many superfluous EC forms). There is a similar root in Kartvelian: PK *ʒeʒw- 'blackthorn, thorny plant' (see Klimov 1964, 234-235, 1971, 229-230; Klimov, however, attracts quite different WC data, namely, PWC *ǯa 'cornel' or PWC *d́ʷVd́ʷV 'awl' - both in fact having other EC parallels). There are also similar forms in Iranian languages (Osset. zaz 'yew', Pers. žāž 'a k. of thorn' et al. - see Abayev 1989, 289 - but despite Abayev, the Iranian source of all these forms is highly dubious).