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!

Gnomish

gwailtha-

verb. to air; expose to air

A word appearing in the Gnomish Lexicon of the 1910s as G. gwailtha- “to air — expose to air”, a verb form of G. gwail “air” from the root ᴱ√gu̯il (GL/45).

Neo-Sindarin: I think this word can be salvaged as a causative verb ᴺS. gwiltha- of the same meaning, from the later version of its root: ᴹ√WIL which still have derivatives related to “air”, such as N. gwelw “air (as a substance)” (Ety/WIL).