| knee-jerk(noun, slang, sick, mad person) |
| knockwurst |
| kook(noun, slang, sick, mad person) |
| loom(noun, slang, sick, mad person) |
| loon(noun, slang, sick, mad person) |
| looneybin(noun, slang, sick, mad person) |
| loony(noun, slang, sick, mad person) |
| loony tune(noun, slang, sick, mad person) |
| luny(noun, slang, sick, mad person) |
| mental(noun, slang, sick, mad person) |
| mishoogeh(noun, slang, sick, mad person) |
| mishugah(noun, slang, sick, mad person) |
| not all there(noun, slang, sick, mad person) |
| nougat(noun, slang, sick, mad person) |
| nut(noun, slang, sick, mad person) |
| nutcase(noun, slang, sick, mad person) |
| nutjob(noun, slang, sick, mad person) |
| nuts(noun, slang, sick, mad person) |
| nutter(noun, slang, sick, mad person) |
| salami |