Gnomish
ilt-
verb. to yoke, join
ilt(h)a-
verb. to yoke, join
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!
A verb appearing as G. ilt- “to yoke, join” in the Gnomish Lexicon of the 1910s (GL/50), likely based on the early root ᴱ√YḶTḶ (QL/106).
Neo-Sindarin: For purposes of Neo-Eldarin I adapt this early root as ᴺ√YALTA “yoke”, so I would adapt the Gnomish verb as ᴺS. ialtha- “to yoke”. For “to join” I would use ᴺS. ianna-.