Definition: not representative of a group, class, or type
Usage: a group that is atypical of the target audience; a class of atypical mosses; atypical behavior is not the accepted type of response that we expect from children
Similar words: unrepresentative
Definition: not exemplifying a class
Usage: I soon tumbled to the fact that my weekends were atypical; behavior quite unrepresentative (or atypical) of the profession