Synonyms of frightful in English:

frightful


See US English definition of frightful

See UK English definition of frightful

See Spanish definition of horroroso

adjective

1‘he had some frightful wounds’

SYNONYMS
horrible, gruesome, grisly, ghastly, hideous, grim, revolting, repulsive, disgusting, horrendous, grievous, dreadful, terrible, nasty, dire, unspeakable
alarming, shocking, terrifying, harrowing, appalling, daunting, unnerving, fearful, fearsome
informal horrid, beastly
archaic, humorous parlous
ANTONYMS

mild

2‘the children were making a frightful racket’

SYNONYMS
awful, very bad, terrible, dreadful, appalling, ghastly, nasty, abominable
unpleasant, disagreeable, lamentable, deplorable, insufferable, unbearable, annoying, irritating
informal beastly, godawful
ANTONYMS

pleasant