moron
[noun]
Synonyms: fool, blockhead, cretin, dunce, dunderhead, halfwit, idiot, imbecile, oaf

[TahlilGaran] English Synonym Dictionary ▲

mo‧ron /ˈmɔːrɒn $ -rɑːn/ noun [countable]
[Date: 1900-2000; Language: Greek; Origin: moros 'of low intelligence']

1. informal not polite a very offensive word for someone who you think is very stupid Synonym : idiot:
Don’t leave it there, you moron!

2. technical old-fashioned someone whose intelligence has not developed to the normal level
—moronic /məˈrɒnɪk $ -ˈrɑː-/ adjective:
a moronic grin

[TahlilGaran] Dictionary of Contemporary English ▲