ad-

ad- [ad, əd, id]

[L ad-, to, at, toward; akin to AT¹] prefix

motion toward, addition to, nearness to [adsorb, adjoin, adrenal]: In words of Latin origin it becomes ac- before c or q; af- before f; ag- before g; al- before l; an- before n; ap- before p; ar- before r; as- before s; at- before t; and a- before sc, sp, or st: many apparent English instances of this prefix are Latinizations, often erroneous, of French or even of English words: See ADVANCE, ADMIRAL, ACCURSED, ACKNOWLEDGE