| vacant(adjective, dull, clear, free, harsh) |
| empty(adjective, dull, clear, free, harsh) |
| fatuous(adjective, stupid, thoughtless) |
| blank(adjective, clear, full, thoughtless, empty) |
| inane(adjective, dull, simple, careless, silly) |
| dull(adjective, quiet, flat, careless, foolish) |
| silly(adjective, informal, careless, indifferent, foolish) |
| mindless(adjective, careless, silly, stupid, thoughtless) |
| hollow(adjective, unsubstantiality) |
| void(adjective, clear, free, smooth, harsh) |
| foolish(adjective, careless, indifferent, silly, stupid) |
| expressionless |
| empty-headed(adjective, careless, indifferent, stupid, full) |
| meaningless(adjective, dull, simple, silly, stupid) |
| stupid(adjective, dull, simple, slow, careless) |
| bare(adjective, clear, free, smooth, full) |
| asinine |
| dumb(adjective, simple, slow, stupid, empty) |
| thoughtless(adjective, careless, indifferent, stupid, blank) |
| unoccupied(adjective, clear, free, bare, thoughtless) |