Meaning

noun uncastrated adult male horse

adjective constituting the full quantity or extent; complete

adjective constituting the undiminished entirety; lacking nothing essential especially not damaged; - Bacon

originFrom Middle English entere, enter, borrowed from Anglo-Norman entier, from Latin integrum, accusative of integer (“whole”), from Proto-Italic *əntagros (“untouched”). Doublet of entier and integer.

Etymology from Wiktionary, CC BY-SA 3.0