Hinterbein vs. Hinterlauf
While both Hinterbein and Hinterlauf generally translate to "hind leg" in English, the difference lies in the context and the specific animal being described. Hinterbein is the general anatomical term, while Hinterlauf is rooted in hunting terminology and applies to specific mammals.
Hinterbein
B1This is the neutral, standard term for "hind leg" that can be used for any animal, including insects, reptiles, and domestic farm animals. It is also the correct term when referring to the rear legs of inanimate objects like furniture.
Die Heuschrecke nutzt ihre kräftigen Hinterbeine zum Springen.
(The grasshopper uses its powerful hind legs to jump.)
Das Pferd hat sich am linken Hinterbein verletzt.
(The horse injured itself on the left hind leg.)
Dieser antike Stuhl wackelt, weil das rechte Hinterbein kürzer ist.
(This antique chair wobbles because the right hind leg is shorter.)
Die Katze kratzte sich mit dem Hinterbein am Kopf.
(The cat scratched its head with its hind leg.)
Hinterlauf
C1This term comes from Jägersprache (hunters' jargon) and refers specifically to the hind legs of game animals (such as deer, wild boars, and rabbits) and dogs. It derives from the verb laufen (to run), emphasizing the leg's function in running.
Der Schäferhund hat Probleme mit seinen Hinterläufen.
(The German Shepherd has problems with his hind legs.)
Ein Feldhase richtete sich auf seine Hinterläufe auf, um besser zu sehen.
(A hare raised itself onto its hind legs to see better.)
Der Jäger bemerkte, dass der Hirsch am rechten Hinterlauf hinkte.
(The hunter noticed that the stag was limping on its right hind leg.)
Wölfe haben sehr muskulöse Hinterläufe, die ihnen Ausdauer verleihen.
(Wolves have very muscular hind legs that give them stamina.)
Summary
Use Hinterbein as the default term for all animals, insects, and objects. Use Hinterlauf specifically when discussing dogs or game animals (like deer and hares) to sound more authentic or technical regarding their anatomy.