The headword is a feminine noun in the nominative (and vocative) singular; cf. nu 490, nu 491, and see generally LSJ s.v. It is perhaps generated by the genitive singular noshlei/as at Sophocles, Philoctetes 39 (web address 1): Neoptolemus [Author, Myth] finds heavily stained rags that have clearly been used to bandage some seriously wounded person.
[1] The (incongruous) gloss is an abstract feminine noun in the nominative (and vocative) singular (lack of strength, weakness, sickliness); see LSJ s.v. As a comparandum Adler also cites the unpublished Ambrosian Lexicon (340).
[2] The adjective nosh/lia is the neuter nominative, vocative, and accusative plural form of nosh/lios, -a, -on, of or for sickness; see LSJ s.v. and an instance with the sense of food for sick persons at Oppian, Halieutica 1.301, with scholion.