Synonyms for Overdress (same or very similar meaning)
WordNet sense 1 (dress excessively):
overclothe
WordNet sense 2 (put on special clothes to appear particularly appealing and attractive):
attire, prink, get up, dress up, deck out, deck up, fancy up, fig out, fig up, gussy up, tog out, tog up, trick out, trick up
From the ODE community, based on WordNet
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