Strong's H8478 · Hebrew

tachath

takh'-ath

from the same as 8430; the bottom (as depressed); only adverbially, below (often with prepositional prefix underneath), in lieu of, etc.

Scholarly Lexicons

Brown-Driver-Briggs (BDB)

 H8478 תַּחַת the under part , hence as adv. accus . and prep . underneath , below , instead of  

Brown-Driver-Briggs Hebrew Lexicon (BDB), 1906 — public domain