Esek
ESEK (ē’sĕk, Heb. ‘ēseq, contention). The name that Isaac gave to a well his servants dug in the Valley of Gerar and that the herdsmen of Gerar struggled for, claiming it belonged to them (Gen.26.20).
ESEK ē’ sĕk (עֵ֔שֶׂק ; contention; LXX ̓αδικία; offense, wrong). An artesian well dug by Isaac’s servants in the valley near Gerar. Rather than quarrel with the native herdsmen, Isaac moved on, digging two more wells before he established an undisputed claim (Gen 26:19-22). The site is unknown.
International Standard Bible Encyclopedia (1915)
(eseq; Septuagint Adikia):
The name given by Isaac to a well dug by his servants, for the use of which the herdsmen of Gerar strove with them-- "contention" (Ge 26:20). It lay in the neighborhood of Rehoboth and Gerar: but the site is not identified.