[1] The headword, which has the same glossing in some other lexica (references at Photius epsilon454 Theodoridis), is third person singular, aorist indicative active, of kni/zw (LSJ entry at web address 1). It must be extracted from somewhere (other than the quotation given, which has the corresponding imperfect); Theodoridis suggests Pindar, Pythian Odes 11.23, but the possibilities also include Aristophanes, Wasps 1286. For the verb see already epsilon 514 and again kappa 1874 and kappa 1875.
[2] Appian, Iberica 150; again under sigma 1693.