congratulate
v.v. to tell someone you are happy for them because they did something well or something good happened. You usually say this when a friend gets a new job or passes a test.
v. to express praise or pleasure to someone on the occasion of their success or good fortune. Transitive; requires a direct object representing the person being praised.
I want to congratulate you on your promotion.
The manager gathered the entire team to congratulate them on finishing the project ahead of schedule.
While it is customary to congratulate the winning candidate immediately, the opposition leader waited until the final tally was officially certified before making the phone call.
First attested in 1548; borrowed from Latin congrātulātus, the perfect active participle of Latin grātulor (“to wish joice, rejoice (with); to congratulate”) (see -ate (verb-forming suffix)), from con- + grātulor, from grātus (“grateful, pleasing, agreeable, beloved”) + -or. By surface analysis, con- + gratulate.
The verb is transitive and takes the preposition 'on' before the reason for the praise.
congratulate for your successcongratulate on your successCongratulate takes the preposition 'on' rather than 'for' when introducing the achievement.