Unmarked

In linguistics and social sciences, markedness is the state of standing out as unusual or difficult in comparison to a more common or regular form. In a marked–unmarked relation, one term of an opposition is the broader, dominant one. The dominant default or minimum-effort form is known as unmarked; the other, secondary one is marked. In other words, markedness involves the characterization of a "normal" linguistic unit against one or more of its possible "irregular" forms.

In linguistics, markedness can apply to, among others, phonological, grammatical, and semantic oppositions, defining them in terms of marked and unmarked oppositions, such as honest (unmarked) vs. dishonest (marked). Marking may be purely semantic, or may be realized as extra morphology. The term derives from the marking of a grammatical role with a suffix or another element, and has been extended to situations where there is no morphological distinction.

In social sciences more broadly, markedness is, among other things, used to distinguish two meanings of the same term, where one is common usage (unmarked sense) and the other is specialized to a certain cultural context (marked sense).

In statistics and psychology, the social science concept of markedness is quantified as a measure of how much one variable is marked as a predictor or possible cause of another, and is also known as Δp (deltaP) in simple two-choice cases.

In terms of lexical opposites, marked form is a non-basic, often one with inflectional or derivational endings. Thus, a morphologically negative word form is marked as opposed to a positive one: happy/unhappy, honest/dishonest, fair/unfair, clean/unclean and so forth. Similarly, unaffixed masculine or singular forms are taken to be unmarked in contrast to affixed feminine or plural forms: lion/lioness, host/hostess, automobile/automobiles, child/children. An unmarked form is also a default form. For example, the unmarked lion can refer to a male or female, while lioness is marked because it can refer only to females.

The default nature allows unmarked lexical forms to be identified even when the opposites are not morphologically related. In the pairs old/young, big/little, happy/sad, clean/dirty, the first term of each pair is taken as unmarked because it occurs generally in questions. For example, English speakers typically ask how (old, big, happy, or clean) something or someone is; use of the marked term (how young are you?) would presuppose youth, smallness, unhappiness, or dirtiness, respectively.

...
Wikipedia