Spanish word cumplimiento comes from Latin con-, Latin pleo (To fill, to fulfill.)

Detailed word origin of cumplimiento

Dictionary entry	Language	Definition
con-	Latin (lat)	Used in compounds to indicate a being or bringing together of several objects. Used in compounds to indicate the completeness, perfecting of any act, and thus gives intensity to the signification of the simple word.
pleo	Latin (lat)	To fill, to fulfill.
compleo	Latin (lat)	(of a promise) I fulfil.. (with food or drink) I fill, sate; satisfy.. I cover, overwhelm.. I fill up, fill full, fill out; make up, complete.. I finish, complete.
cumplir	Spanish (spa)	To complete. To fulfil. To turn a certain age (usually succeeded by los).
cumplimiento	Spanish (spa)	Compliance. Formality. Fulfillment, completion.