con·grat·u·late 
(kən-grăchə-lāt′, -grăj-, kəng-)
(kən-grăchə-lāt′, -grăj-, kəng-)tr.v. con·grat·u·lat·ed, con·grat·u·lat·ing, con·grat·u·lates
To express one's joy or good wishes to (someone) regarding that person's achievement or good fortune: congratulated her on her promotion.
[Latin congrātulārī, congrātulāt- : com-, com- + grātulārī, to rejoice (from grātus, pleasing; see gwerə-2 in the Appendix of Indo-European roots).]
con·gratu·la′tor n.
con·gratu·la·to′ry (-lə-tôr′ē) adj.