again, from AHD:

USAGE NOTE: Brunette was for a long time used to denote a woman having a dark complexion; now it is used chiefly in reference to hair color. The general practice is to use the form brunette to refer only to women, with brunet as a less frequently used variant that can be applied as well to men and mixed groups. The distinction, like the one between blonde and blond, has been regarded as carrying sexist implications. In this case, however, it is difficult to see how the problem can be easily resolved. It is unlikely that brunette could be pressed into service as a neutral term, since the suffix -ette is too closely associated with marked feminine gender. Brunet is theoretically available for both sexes but is rarely applied to men, whose corresponding coloration is typically described simply as “brown.” It would, of course, be possible to use brown for the hair color of both sexes, if only that word could be redeemed from the associations of drabness that led to the adoption of the substitute brunette in the first place. See Usage Note at blond.

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