Linguistics. (of a phoneme) characterized by the presence of a phonological feature that serves to distinguish it from an otherwise similar phoneme lacking that feature, as (d), which, in contrast to (t), is characterized by the presence of voicing. characterized by the presence of a marker indicating the grammatical function of a construction, as the plural in English, which, in contrast to the singular, is typically indicated by the presence of the marker -s. specifying an additional element of meaning, in contrast to a semantically related item, as drake in contrast to duck, where drake specifies “male” while duck does not necessarily specify sex. occurring less typically than an alternative form, as the word order in Down he fell in contrast to the more usual order of He fell down. Compare unmarked (def 2).