-ad definition

<suffix>

A suffix used to form nouns in collective numerals (myriad; triad), feminine patronymics (Dryad), and in names of poems and similar compositions (Iliad; Dunciad; jeremiad).

Origin: Greek -as -ada

(06 Feb 2009)

<prefix>

As a prefix ad- assumes the forms ac-, af-, ag-, al-, an-, ap-, ar-, as-, at-, assimilating the d with the first letter of the word to which ad- is prefixed.

It remains unchanged before vowels, and before d, h, j, m, v.

Examples include: adduce, adhere, adjacent, admit, advent, accord, affect, aggregate, allude, annex, appear, etc. It becomes ac- before qu, as in acquiesce.

Also 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: via Old French a-, from Latin ad meaning to, towards.

(05 Feb 2009)