Real Dictionary

slur
countable noun: A slur is an insulting remark which could damage someone's reputation.
verb: If someone slurs their speech or if their speech slurs, they do not pronounce each word clearly, because they are drunk, ill, or sleepy.

slur in American English
the act or process of slurring
to pass over quickly and carelessly; make little of
intransitive verb: to read, speak, or sing hurriedly and carelessly
noun: a slurred utterance or sound
transitive verb: to pass over lightly or without due mention or consideration

slur in British English
noun: an indistinct sound or utterance
verb: to treat superficially, hastily, or without due deliberation; gloss