Beware, older languages below! The languages below were invented during Tolkien's earlier period and should be used with caution. Remember to never, ever mix words from different languages!
allane
pronoun. nobody, nothing (no thing), no one
alle
pronoun. nobody, nothing (no thing), no one
lálane
pronoun. nobody, nothing (no thing), no one
(a)láqainen
adverb. by no means
A correlative combination appearing as {láqainen >>} ᴹQ. (a)láqainen “by no means” in Demonstrative, Relative, and Correlative Stems (DRC) from 1948 (PE23/111), a combination of ᴹQ. láqa “none” and the instrumental suffix ᴹQ. -nen.
Neo-Quenya: For purposes of Neo-Quenya I would update this to ᴺQ. allanen “by no means” using later ᴹQ. alla “none”, also from DRC.
The correlative combinations ᴹQ. {aláqe, lāqe >>} alle, allane “nobody, nothing, no one” appeared Demonstrative, Relative, and Correlative Stems (DRC) from 1948 (PE23/103 and note #41), proniminal forms of ᴹQ. alla “none”. There was also an archaic variant form †lálane and a more elaborate form ᴹQ. láqane “nobody, at all”. Drafts has laqe “nobody” in the phrase ᴹQ. tasse ni·kenne laqe imma “there I saw nobody whatsoever” (PE23/101-102 note #36).
Neo-Quenya: For purposes of Neo-Quenya I would use ᴺQ. alquen for “nobody, no one”, inspired by Q. ilquen “everbody”. Other neologisms for “nobody” include ᴺQ. alaquen from the NQW and ᴺQ. úquen from ABNW (ABNW) from the early 2000s. For “nothing” I would just use ᴹQ. alla.