A coverb is a word or prefix that resembles a verb or co-operates with a verb. In languages that have the serial verb construction, coverbs are a type of word that shares features of verbs and prepositions. A coverb takes an object or complement and forms a phrase that appears in sequence with another verb phrase in accordance with the serial construction. A coverb appears to be subordinate to a main verb and fulfills a function similar to that of a preposition.
Some words that may be classed as coverbs can also function as independent verbs, but that is not always the case. Coverbs in that sense are found in Asian languages such as Chinese and Vietnamese, and, for example, West African languages such as Yoruba. § Examples are given below.
The term coverb (like preverb) is also sometimes used to denote the first element in a compound verb or complex predicate. There, the coverb supplies significant semantic information, and the second element (a light verb) is inflected to convey mainly grammatical information. The term is used in this way in relation to, for instance, North Australian languages.
In relation to Hungarian, coverb is sometimes used to denote a verb prefix. They are elements that express meanings such as direction or completion and so have a function corresponding to that of certain types of adverbs.
The following examples demonstrate the usage of coverbs in Standard Chinese. They illustrate the first—probably most common—of the three above meanings for the term.
The above sentence represents a typical Chinese serial verb construction, with two consecutive verb phrases meaning "help you" and "find him", sharing the same subject ("I"), and essentially referring to the same action. The meaning of the "help you" phrase, however, is closer in this context to the English prepositional phrase "for you". Thus, the word bāng, while it may be analyzed as a verb meaning "help", actually has a function closer to that of a preposition meaning "for". It is words like bāng, as used in the above sentence, that are referred to as coverbs in descriptions of Chinese (and of other languages, like Vietnamese and Yoruba, which have analogous structures).
In the above example, there are three coverbs: zuò (here having the prepositional meaning "by"); cóng (meaning "from"); and dào (here meaning "to"). Although certain Chinese coverbs can also be used as main verbs, others are not normally so used. Of those that appear here, zuò can be a verb meaning "sit", and dào can be a verb meaning "arrive", but cóng is almost always used as a coverb meaning "from", not as a verb.
Since coverbs precede their complement (object) and perform essentially a prepositional function, some linguists simply refer to them as prepositions. In Chinese, they are called jiè cí (介词; 介詞), a term which generally corresponds to "preposition" (or more generally, "adposition"). The situation is complicated somewhat by the fact that Chinese has location markers that appear after a noun that are often called postpositions.
The meaning of an English locational preposition is often conveyed by a coverb and location marker in combination, as in 在桌子上 zài zhuōzi shàng, "on the table", literally "at table-on". However, in most situations, the grammatical behavior of the location markers resembles that of nouns rather than verbs or adpositions.