proclitic

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. A clitic that is attached to the beginning of another word.
2. adj. Of or relating to a proclitic or proclisis; forming an accentual unit with the following word.

Century Dictionary and Cyclopedia

1. In Greek grammar, dependent in accent upon the following word: noting certain monosyllabic words so closely attached to the word following as to have no accent.
2. n. In Greek grammar, a monosyllabic word which leans upon or is so closely attached to a following word as to have no independent accent. The proclitics are certain forms of the article, certain prepositions and conjunctions, and the negative οὐ. Compare atonic.

Wiktionary

1. n. linguistics A clitic which phonetically joins with the following word. In English, the dialectal form t' is an example. In Arabic, conjunctions and prepositions that have only one letter, such as و (wa-), always attach as a prefix to the following word.

GNU Webster's 1913

1. adj. (Gr. Gram.) Leaning forward; -- said of certain monosyllabic words which are so closely attached to the following word as not to have a separate accent.