The Collaborative International Dictionary of English v.0.48:

Tonsillectomy \Ton`sil*lec"to*my\, n. (Surg.)
   The operation of removing the tonsils; -- formerly also
   called tonsilotomy.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Tonsilotomy \Ton`sil*ot"o*my\, n. (Surg.)
   The operation of removing the tonsils, or a portion thereof;
   -- called more commonly tonsillectomy.
   [1913 Webster]

WordNet (r) 3.0 (2006):

tonsillectomy
    n 1: surgical removal of the palatine tonsils; commonly
         performed along with adenoidectomy

Moby Thesaurus II by Grady Ward, 1.0:

33 Moby Thesaurus words for "tonsillectomy":
   adenoidectomy, appendectomy, arteriectomy, castration,
   cholecystectomy, craniectomy, cricoidectomy, cystectomy,
   enterectomy, gastrectomy, hemorrhoidectomy, hysterectomy,
   mammectomy, mastectomy, mastoidectomy, nephrectomy, omphalectomy,
   oophorectomy, oophorocystectomy, orchidectomy, ovariectomy,
   pancreatectomy, penectomy, pericardiectomy, phrenicectomy,
   pneumonectomy, prostatectomy, salpingectomy, stapedectomy,
   ureterectomy, urethrectomy, vasectomy, venectomy