n.
Variant: or ac- or af- or ag- or al- or ap- or as- or at-
Function: prefix
Etymology: Middle English, from Anglo-French & Latin; Anglo-French, from Latin, from ad ― more at AT
1 : to : toward ― usually ac- before c, k, or q < ac culturation> and af- before f < af fluent> and ag- before g < ag gradation> and al- before l < al literation> and ap- before p < ap portion> and as- before s < as suasive> and at- before t < at tune> and ad- before other sounds but sometimes ad- even before one of the listed consonants < ad sorb>
2 : near : adjacent to ― in this sense always in the form ad- < ad renal>