Толковый словарь английского языка Oxford English Reference - ad

n. colloq. an advertisement. Etymology: abbr. AD abbr. (of a date) of the Christian era. Usage Strictly, AD should precede a date (e.g. AD 410), but uses such as the tenth century AD are well established. Etymology: Anno Domini, 'in the year of the Lord' AD 1. suffix forming nouns: 1 in collective numerals (myriad; triad). 2 in fem. patronymics (Dryad). 3 in names of poems and similar compositions (Iliad; Dunciad; jeremiad). Etymology: Gk -as -ada 2. suffix forming nouns (ballad; salad) (cf. -ADE(1)). Etymology: F -ade