There are quite a few idioms in English to describe people who are a bit crazy or not very intelligent. In some something is lacking – a sandwich short of a picnic, a few beers short of a six-pack, one brick short of a load, not playing with a full deck and so on. In some animals are loose somewhere, like having bats in the belfry, or kangaroos loose in the top paddock.
Others include out to lunch, as nutty as a fruit cake, as crazy as a sack full of ferrets, as mad as a hatter, to have a screw loose, not the sharpest knife in the drawer, and not hitting on all six cylinders.
Here are some examples in other languages, some of which seem as crazy to me as the imaginary person being described:
- Croatian – Vrane su mu popile mozak – Crows have drunk his brain
- Czech – Šplouchá mu na maják – It’s splashing on his lighthouse
- French – avoir une araigneé au plafond – to have a spider on the ceiling
- Indonesian – otak udang – shrimp brained
- Italian – Non avere tutti i venerdì – to be lacking some Fridays
- Latvian – Caurs jumts – the roof is full of holes
- Polish – Brak mu piątej klepki – he’s/ missing the fifth stave
- Portuguese - Tem macaquinhos no sotão - (He) has little monkeys in the attic
- Spanish – Más loco que una cabra / un plumero – Crazier than a goat / feather duster
- Turkish – Keçileri kaçırmıs – His goats fled