K. Reshetnikov's notes:The comparison with FB is suggested by me (Resh.). For semantics cf. the meaning attested in North Sam.: we may deal with development 'hide oneself' > 'disappear' (> 'get lost', 'be drowned', 'perish' etc.; cf. also the meaning 'to be (partly) hidden from view by smth.'). Ur. *šukkV-. Despite Rédei, it is better to keep the Sam. word (with its probable cognates) apart from Hun. csuk- 'to close, to lock' (because of cs- < *c'- in Hun.) comparing the latter with Udm. c'uka- 'to obstruct, block, bar; to detain, hamper' (cf. КЭСКЯ 312-313).