Differential Object Marking

Differential object marking (DOM) is a linguistic phenomenon that is present in more than 300 languages; the term was coined by Georg Bossong. In languages where DOM is active, direct objects are divided in two different classes, depending on different meanings, and, in most DOM languages, only one of the classes receives a marker, the other being unmarked (but there are languages, like Finnish, where both types of objects are marked with different endings).

A well-known DOM language is Spanish. In Spanish, direct objects that are both human and specific require a special marker (the preposition a "to"):

Inanimate direct objects do not usually allow this marker, even if they are specific:

Yet, some animate objects that are specific can optionally bear the marker:

Some dialectal variation has been attested regarding the use of DOM in different varieties of Spanish. Balasch finds that, while the linguistic factors conditioning the use of DOM remain the same in both Mérida (Venezuela) Spanish and Madrid Spanish, DOM appears much more often in Madrid data. Furthermore, Tippets and Schwenter find that a factor known as relative animacy (the animacy of the direct object relative to that of the subject) is quite important in the implementation of DOM in varieties of Spanish such as Buenos Aires and Madrid Spanish.

Other examples of languages with differential object marking are Persian, Turkish, Copala Triqui, Khasi, Tamil, Malayalam, Kham, Hebrew and Amharic. In Turkish, the direct object can either have accusative case or have no (visible) case at all; when it has accusative case, it is interpreted as specific (e.g. one specific person), and otherwise it is interpreted as nonspecific (e.g. some person).

This is different from what happens in non-DOM languages, where all direct objects are uniformly marked in the same way; for instance, a language could mark all direct objects with an accusative ending (as in Quechua); other language could leave all direct objects without overt marker (as in English).

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