undertakingundertaking: a legal promise to do some positive act, or to ...: a legal promise to do some positive act, or to abstain from doing something; a binding undertakingundertaking: a legal promise to do some positive act, or to ... will create a legal obligation on the giver of the undertakingundertaking: a legal promise to do some positive act, or to ... in accordance with its terms; for example, in the context of restraint of traderestraint of trade: a restriction on a party’s right to ca... and restrictive covenants, an undertakingundertaking: a legal promise to do some positive act, or to ... not to compete or not to solicit customers or staff for a certain period of time.