Definition of: ad- prefix

To; toward; near: adhere, advert, adrenal; often, in English, without perceptible force. Also: a- before sc, sp, st, as in ascribe; ab- before b, as in abbreviate; ac- before c, q, as in acquire; af- before f, as in afferent; ag- before g, as in agglutinate; al-before l, as in allude; an- before n, as in annex; ap- before p, as in append; ar- before r, as in arrive; as- before s, as in associate; at-before t, as in attract. [<L ad- <ad to]