Synonyms for Skeleton (same or very similar meaning)
WordNet sense 1 (a scandal that is kept secret):
skeleton in the closet, skeleton in the cupboard
WordNet sense 2 (the hard structure (bones and cartilages) that provides a frame for the body of an animal):
frame, skeletal system, systema skeletale
WordNet sense 3 (the internal supporting structure that gives an artifact its shape):
underframe, skeletal frame
From the ODE community, based on WordNet
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