1. Unpleasantly loud and noisy: "There are those who find the trombones blatant and the triangle silly, but both add effective color" (Musical Heritage Review). See Synonyms at vociferous.
2. Usage Problem Totally or offensively conspicuous or obtrusive: a blatant lie.

Usage Note: It is not surprising that blatant and flagrant are often confused, since the words have overlapping meanings. Both attribute conspicuousness and offensiveness to certain acts. Blatant emphasizes the failure to conceal the act. Flagrant, on the other hand, emphasizes the serious wrongdoing inherent in the offense. Certain contexts may admit either word depending on what is meant: a violation of human rights might be either blatant or flagrant. If it was committed with contempt for public scrutiny, it is blatant. If its barbarity was monstrous, it is flagrant. · Blatant is sometimes used to mean simply "obvious," as in the blatant danger of such an approach, but this use has not been established and is widely considered an error.