This spell launches an acidic arrow at one enemy, which strikes it for moderate damage. The acid will then 'stick' to the target for a few rounds afterwards, causing light damage until it expires. This is not a poison effect, however. The target cannot be cured, and must wait until the spell's duration expires.
This spell is obviously taken from the Dungeons & Dragons game. The effect and sound is modelled after that of Icewind Dale's Melf's Acid Arrow.