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@PUC: You're right to add it as a derived term; it's not a plural but a collective noun. Compare Serbo-Croatian grana ⇒ granje or kamen ⇒ kamenje with a cognate suffix. The plural is жьзли (žĭzli). — Vorziblix (talk · contribs) 15:58, 5 August 2020 (UTC)Reply