lúva noun "bow, bight; bend, bow, curve" (Appendix E, PE17:122, 168). The reference is to a "bow" as part of written characters and other uses, but "not for shooting" (a bow used to shoot arrows is called quinga, possibly also cú if the latter term is used as in Sindarin).
Quenya
quinga
bow
lúva
bow, bight; bend, bow, curve
cú
arch, crescent
cú ("k")noun "arch, crescent" (KU3); "crescent Moon" (LT1:271; the long vowel was denoted by a circumflex rather than an accent in the early "Qenya" lexicon). In Sindarin, the same word can be used for a "bow" as used to shoot arrows (but possibly this is only quinga in Quenya).
caw-
bow
#caw- vb. "bow" ("k")(1st pers aorist cawin "I bow") (LT1:257; cf. cauca, cauco). In Tolkien's later Quenya, a verbal stem with w in this position does not seem to fit the general phonology well; intervocalic w would become v. We should perhaps read *cav*- whereever the second consonant of the root follows a vowel, but the nasal-infixed past tense could be canwë with the original quality of the consonant preserved. (Compare such a past tense form as anwë, q.v.) However, Tolkiens later verb luhta**- may be preferred for intransitive "bow".
cuv-
verb. bow
quinga ("q")noun "bow" (for shooting) (KWIG, LT1:256)