The shelf / The head / French

FRENCH

Avoir une araignée au plafond.

“To have a spider on the ceiling.”

MEANS

Not quite all there.

Missing something?

English and German lose something. Russian loses the people at home. French doesn't lose anything. It gains a spider.

Source: Dictionnaire de l'Académie française, Expressio.

On the label: Not all there

Watch it

The film: “Not all there? In French, he's got company.”

The same idea, elsewhere

From “Not all there” to French.

ENGLISHNot all there.The one you know.Phrase Finder, Dictionary.com.
GERMANNicht alle Tassen im Schrank haben.“Not to have all the cups in the cupboard.”Duden.
RUSSIANНе все дома.“Not everyone is at home.”Phraseological Dictionary of the Russian Literary Language.
FRENCHAvoir une araignée au plafond.“To have a spider on the ceiling.”Académie française, Expressio.