(adj) not conforming to the language usage of a prestige group within a community; ; - A.R.Dunlap, Ant. standard, Example:a nonstandard dialect is one used by uneducated speakers or socially disfavored groups; the common core of nonstandard words and phrases in folk speech
(adj) varying from or not adhering to a standard, Ant. standard, Example:nonstandard windows; envelopes of nonstandard sizes; nonstandard lengths of board