@@@ es might be an assimilated form as suggested by Helge Fauskanger (QQ/es)
Qenya
ehta-
verb. to stab
ehtyar
noun. spearman
en
there, yonder, far away; look yon(der); that; in that (future) case
tas
adverb. there
tasse
adverb. there
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 ᴹQ. ehta “stab” based on the root ᴹ√EK “point, sharp point, thorn” appearing on a page of roots from the Quenya Verbal System from 1948, but this page was marked through (PE22/127).
Neo-Quenya: Primitive ✶ektā- “prick with a sharp point, stab” appears in Tolkien’s later writings (WJ/365), so I think ᴺQ. ehta- “to stab” can be retained for purposes of Neo-Quenya.