Quenya
sovalda-
verb. to cleanse, purify
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!
Early Quenya
sovalna-
verb. to cleanse, purify
sovallu-
verb. to cleanse, purify
poita-
verb. to cleanse
A verb appearing ᴱQ. poita- {“cleanse, tidy up, straighten” >>} “cleanse” in the Qenya Lexicon of the 1910s under from the early root ᴱ√POYO (QL/75).
Neo-Quenya: Since ᴹ√POY was still associated with “clean” words in The Etymologies of the 1930s (Ety/POY), I would retain ᴺQ. poita- “to cleanse, ✱clean” for purposes of Neo-Quenya.