Real Dictionary

accent
countable noun: An accent is a short line or other mark which is written above certain letters in some languages and which indicates the way those letters are pronounced.
countable noun: Someone who speaks with a particular accent pronounces the words of a language in a distinctive way that shows which country, region, or social class they come from.
singular noun: If you put the accent on a particular feature of something, you emphasize it or give it special importance.

accent in American English
the emphasis (by stress, pitch, or both) given to a particular syllable or word when it is spoken
noun: prominence of a syllable in terms of differential loudness, or of pitch, or length, or of a combination of these

accent in British English
noun: the characteristic mode of pronunciation of a person or group, esp one that betrays social or geographical origin