[1] : The Collaborative International Dictionary of English v.0.48

malformation \mal`forma"tion\, n. mal- + formation.
   ill formation; irregular or anomalous formation; abnormal or
   wrong conformation or structure; -- often used of body parts
   such as limbs which do not develop properly during fetal
   maturation.
   1913 webster +pjc

[2] : WordNet (r) 2.0

malformation
     n 1: an affliction in which some part of the body is misshapen or
          malformed syn: deformity, misshapenness
     2: something abnormal or anomalous syn: miscreation
see also:
deformity misshapenness miscreation 

[3] : Moby Thesaurus II by Grady Ward, 1.0

49 moby thesaurus words for "malformation":
   absurdity, anticness, bizarreness, bizarrerie, bowlegs, camelback,
   cleft palate, clubfoot, crookback, curiousness, defacement,
   deformation, deformity, disfigurement, distortion, fantasticality,
   flatfoot, freakishness, grotesqueness, grotesquerie, harelip,
   humpback, hunchback, knock-knee, kyphosis, lordosis,
   malconformation, misproportion, misshape, monstrosity,
   monstrousness, mutilation, oddity, outlandishness, peculiarity,
   quaintness, queerness, singularity, splayfoot, strangeness,
   swayback, talipes, teratism, teratology, torticollis, truncation,
   valgus, weirdness, wryneck

Malformation >> M Words
Malformation, definition of term: Malformation
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