ala, #ála (1) imperative particle á, a combined with the negation lá, -la "not" to express a prohibition (VT43:22; see lá #1). Also with 1st person suffix -lyë (alalyë and álalyë, VT43:10, 22, VT44:8) and 1st person pl. object suffix -më (alamë and álamë, "do not [do something to] us", as in álamë tulya, "do not lead us", VT43:12, 22). In the essay Quendi and Eldar, negative imperatives are rather indicated by áva, q.v., but this form can well coexist with ala, #ála.
Early Quenya
(h)áva
pronoun. *its (emphatic possessive)
áva, avá (the latter stressed on the final syllable) "Don't!", negative imperative particle (compare ala, #ála). Cf. ávan "I won't" (also ván, ványë); áva carë! ("k") "don't do it!" (WJ:371)