a translation that has been verified for official use (by courts, government agencies, academic institutions, etc
a verified and accurate translation of the document submitted to us
A certified translation contains the following clause inserted into notorized document, "CERTIFIED TRUE TRANSLATION I, (translator), certify that the following is a true and accurate translation form (language 1 to language 2), done this (date)". And then, it is signed by the translator. An individual can never certify translation done for his or her own materials. Translators will also say that they are certified by certain organizations such as the American Translator's Association. There is no official industry certification.
In the US, a certified translation is one where the translator has signed an oath before a notary public certifying the accuracy and correctness of the translation, as well as the fact that he is qualified to make such a certification. Since in the US, there are no restrictions as to who can or cannot be a translator, anyone willing to swear that he or she is qualified to translate into and from a language pair can certify a translation.