1 make a formal statement of; attest; attest to (certified that he had witnessed the crime).
2 declare by certificate (that a person is qualified or competent) (certified as a trained bookkeeper).
3 officially declare insane (he should be certified).
Phrases and idioms:
certified cheque a cheque the validity of which is guaranteed by a bank. certified mail US = recorded delivery (see RECORD). certified milk milk guaranteed free from the tuberculosis bacillus.
Etymology: ME f. OF certifier f. med.L certificare f. L certus certain
Useful english dictionary. 2012.