A clitic that is attached to the end of another word. In Give 'em the works, the pronoun 'em is an enclitic.
A clitic.
adj. Of or relating to an enclitic or enclisis; forming an accentual unit with the preceding word.
[Late Latin encliticus, from Greek enklitikos, from enklīnein, to lean on : en-, on, in; see en-2 + klīnein, to lean; see klei- in Indo-European roots.] en·clit'i·cize' (-ə-sīz') v., en·clit'i·ci·za'tion (-ə-sĭ-zā'shən), en·clis'is (-klĭs'ĭs) n.