Peculiar can be considered a euphemism for the other three, so that means one of the other three would not be one.
peculiar
ugly hideous repulsive grotesque disgusting
* distorted and unnatural in shape or size; abnormal and hideous; "tales of grotesque serpents eight fathoms long that churned the seas"; "twisted ... * art characterized by an incongruous mixture of parts of humans and animals interwoven with plants * antic: ludicrously odd; "Hamlet's assumed antic disposition"; "fantastic Halloween costumes"; "a grotesque reflection in the mirror"
Grotesque, horrible, grisly, macabre, repulsive, repugnant, revolting, loathsome, ghastly, grim...
horrible, disgusting, grotesque, awful, dreadful, grim, gruesome, horrid, hateful, nasty, morbid, loathsome, monstrous, terrible
ugly, hideous, disfigured, evil-looking, fugly, grotesque, monstroushideous, repulsive, ill-favored, ill-favoured, scrofulous, unlovely, unpicturesque, unsightly
more hideous, most hideous
more hideous, most hideous
Do you think that person is hideous? What a hideous looking doll!
eg: You cant wear that top, it is hideous! Look at his shoes, how hideous!
other words are ugly,bad-looking, beastly, deformed, disfigured, disgusting, frightful, gross, grotesque, hideous, homely, horrid, monstrous, not much to look at, plain, repelling, repugnant, repulsive, revolting, unalluring, unappealing, unsightly
Medusa had a hideous hairdo.