Definition of ad- in English:

ad-

prefix

  • 1Denoting motion or direction to:

    ‘advance’
    ‘adduce’
    1. 1.1 Denoting reduction or change into:
      ‘adapt’
      ‘adulterate’
    2. 1.2 Denoting addition, increase, or intensification:
      ‘adjunct’

Usage

Ad- is also found assimilated in the following forms: a- before sc, sp, st; ac- before c, k, 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

Origin

From Latin ad to; in the 16th century the use of ad- and its variants was extended to replace a- from a different origin such as Latin ab- (e.g. advance, from French avancer based on late Latin abante in front).

Pronunciation:

ad-

/ad//əd/