*leikw- Look up *leikw- at Dictionary.com
Proto-Indo-European root meaning "to leave."

It forms all or part of: delinquent; derelict; eclipse; eleven; ellipse; ellipsis; elliptic; lipo- (2) "lacking;" lipogram; loan; paralipsis; relic; relict; reliction; relinquish; reliquiae; twelve.

It is the hypothetical source of/evidence for its existence is provided by: Sanskrit reknas "inheritance, wealth," rinakti "leaves;" Greek leipein "to leave, be lacking;" Latin linquere "to leave;" Gothic leihvan, Old English lænan "to lend;" Old High German lihan "to borrow;" Old Norse lan "loan."