Complementizer

The term complementizer is used to denote a subordinator that marks a complement clause.

Examples

 * English that, for ... to
 * French ''que
 * Affixes like English -ing
 * Turkish -dik

Comments
The term complementizer is also sometimes used (especially in generative syntax) for other subordinating elements such as adverbial subordinators or even relative particles (because these are assumed to occupy the COMP position, like true complementizers).

Polysemy
The term complementizer or more often its abbreviation COMP, is also used for a structural position in X-bar theory that can be filled by complementizers or other elements (most notably, the finite verb in verb-second languages). See complementizer (in X-bar theory).

Origin
The term was coined by Rosenbaum (1967:24).

Reference

 * Rosenbaum, Peter S. 1967. The grammar of English predicate complement constructions. Cambridge, MA: MIT Press.

Link
Utrecht Lexicon of Linguistics

Other languages
German Komplementierer Russian номинализатор