The Collaborative International Dictionary of English v.0.48:
Adjunction \Ad*junc"tion\, n. [L. adjunctio, fr. adjungere: cf. F. adjonction, and see Adjunct.] The act of joining; the thing joined or added. [1913 Webster]WordNet (r) 3.0 (2006):
adjunction n 1: an act of joining or adjoining things [syn: junction, adjunction]