Synonyms for Hideous (same or very similar meaning)
WordNet sense 1 (grossly offensive to decency or morality; causing horror):
horrid, horrific, outrageous
WordNet sense 2 (unpleasant or disgusting especially to the senses):
offensive
WordNet sense 3 (so extremely ugly as to be terrifying):
repulsive
WordNet sense 4 (displeasing to the senses):
ugly
From the ODE community, based on WordNet
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