WordNet (r) 3.0 (2006):

eat away
    v 1: remove soil or rock; "Rain eroded the terraces" [syn:
         erode, eat away, fret]
    2: wear away or erode [syn: fret, eat away]

Moby Thesaurus II by Grady Ward, 1.0:

45 Moby Thesaurus words for "eat away":
   abate, abrade, abstract, bate, bite, canker, corrode, curtail,
   decrease, deduct, depreciate, derogate, detract, diminish,
   disparage, drain, eat, eat into, erode, extract, file away, gnaw,
   impair, leach, lessen, nibble away, oxidize, purify, reduce,
   refine, remove, retrench, rub away, rust, scour, shorten, subduct,
   subtract, take away, take from, thin, thin out, wear away, weed,
   withdraw