Source: Hart, pp. 144-145; Whitney pp. 395-400 (§§ 1076-1089)

This table lists the common prefixes affixed to verb roots in Sanskrit along with their meaning in English. In most cases, the prefix changes the meaning of the root in such unpredictable ways that one has to memorize the meaning of each combination separately. It is only in hindsight that one can see why a certain prefixed verb has a particular meaning. Some prefixed especially the intensifiers scarcely change the meaning of the root at all. Multiple prefixes can be added simultaneously. For instance, उपागम् is उप + आ + गम्. The most common prefixes are:

Prefix Meaning
अति- across, beyond, past, over, to excess
अधि-  above, over, on, onto
अनु-  after, along, toward, in imitation of
अन्तर्- between, among, within.
अप- away, forth, off
अभि- to, towards, into, unto, against (often with implied violence), approaching
अव- down, off
आ- to, unto, at
उद्- up, up out
उप- to, toward
नि- down; in, into
निस्- out, forth
परा- to a distance, away, forth
परि- round about, around, (intensifier)
प्र- forward, onward, forth, fore
प्रति- in reversed direction, back to or against, in return
वि- apart, asunder, away, out, (intensifier)
सम्- along, with, together, (intensifier)

Rarer and more distinctly adverbial prefixes which are akin to the above are:

Prefix Meaning
 अछ-, अछा- to, unto
 अविस्- forth to sight, in view
 तिरस्- through, crossways, out of sight
 पुरस्- in front, forward
प्रदुस्- forth to view
बहिस्- outside
विना- without
अलम्- sufficiently, properly
साक्षत्- in view