Strong's #5226: hipeiko (pronounced hoop-i'-ko)
from 5259 and eiko (to yield, be "weak"); to surrender:--submit self.
Thayer's Greek Lexicon:
1) to resist no longer, but to give way, yield (of combatants)
2) metaphorically to yield to authority and admonition, to submit
Part of Speech: verb
Relation: from G5259 and eiko (to yield, be "weak" )
This word is used 1 times:
Hebrews 13:17: "them that have the rule over you, and submit yourselves: for they watch for"