Synonyms of retardo

1 Syllable
slow, dim, dull, weak
2 Syllables
dummy, numbskull, simple, dumbbell, backward, stupid, gorked, dumbo, dopey, touched, sappy, yo-yo, pinhead, dumdum
3 Syllables
birdbrained, slow-witted, subnormal, dim-witted, retarded, moronic, half-witted, opaque
4 Syllables
lamebrained, imbecile, defective, exceptional, feeble-minded, simple-minded
5 Syllables
underachieving