A word appearing in Early Noldorin Word-lists of the 1920s, first given as uvlam “dumb” in the (untranslated) phrase maint uvlam o ballam “✱better dumb than evil-tongued”, which was then revised to maint orlham o vallam, although uvlam as an independent word was allowed to stand (PE13/138). The revision clearly relates to Tolkien’s decision to change the negative prefix from ᴱN. um- to ᴱN. ur-/or- in this document (PE13/155). The second element of uvlam/orlham is ᴱN. lham(b) “tongue” (PE13/148).
Neo-Sindarin: For purposes of Neo-Sindarin, I would update this word to ᴺS. úlam “dumb, unable to speak, (lit.) untongued” using the later negative prefix ú-.
úpa adj. "dumb" (i.e. unable to speak) (PE17:126)