To make a clumsy, tactless, or embarrassing remark or action without intending to. This is by far the most common use of the word.
example
Als ich sie nach ihrem Mann fragte, trat ich voll ins Fettnäpfchen, denn sie waren frisch geschieden.
When I asked her about her husband, I really put my foot in it, because they had just gotten divorced.
Usage tips
Compound word
The word consists of 'Fett' (fat) and 'Näpfchen', the diminutive form of 'der Napf' (a small bowl). It originally referred to a small bowl of fat that used to stand in kitchens.
EXAMPLE
Die Redewendung stammt aus einer Zeit, als man aus Versehen in ein auf dem Boden stehendes Fettnäpfchen treten konnte.
The idiom comes from a time when you could accidentally step into a small pot of fat standing on the floor.
Fixed expression
This word is used almost only in the fixed idiom 'ins Fettnäpfchen treten' (to put one's foot in it). It means to behave clumsily or tactlessly without meaning to.
EXAMPLE
Mit meiner Frage nach seiner Ex-Freundin bin ich wirklich ins Fettnäpfchen getreten.
With my question about his ex-girlfriend, I really put my foot in it.
Intensifying the expression
The idiom can be intensified with adverbs like 'voll' (completely/really), 'richtig' (really/properly), or 'gehörig' (thoroughly) to emphasize how big the embarrassing mistake was.
EXAMPLE
Er hat mit seiner Bemerkung über ihr Alter voll ins Fettnäpfchen getreten.
With his comment about her age, he really put his foot in it.
Register: rare meaning
The literal meaning of 'Fettnäpfchen' (small fat pot) as a container for fat is outdated today. It is now used almost only in historical descriptions or in museums.
EXAMPLE
In der Ausstellung zur Küchengeschichte war auch ein altes Fettnäpfchen aus Ton zu sehen.
In the exhibition on kitchen history, there was also an old clay fat pot on display.
Compare with
near_synonym · confusable
Fettnäpfchen vs Missgeschick
mishap
'das Missgeschick' and 'das Fettnäpfchen' both have to do with embarrassing situations. 'Missgeschick' is a general small mishap or mistake, for example when something falls down or you do something wrong. 'Fettnäpfchen' is almost always used in the phrase 'ins Fettnäpfchen treten' (to put one's foot in it). This means a clumsy or tactless remark or action when dealing with other people. The words can be confused because both can be embarrassing. The difference is: a 'Missgeschick' can be something practical that happens; a 'Fettnäpfchen' is usually socially embarrassing.
Fettnäpfchen
Herr Braun tritt leicht ins Fettnäpfchen, wenn er über private Themen spricht.
Mr. Braun easily puts his foot in it when he talks about private topics.
Missgeschick
Im Restaurant passierte ein Missgeschick, als der Kellner ein Glas fallen ließ.
A mishap happened in the restaurant when the waiter dropped a glass.