A German shepherd is a large, usually fierce dog that is used to guard buildings or by the police to help them find criminals.
[mainly US]regional note: in BRIT, also use Alsatian
...his eighty-five-pound German shepherd Spike.
German shepherd in British English
or German shepherd dog or German sheep dog
noun
another name for Alsatian (sense 1)
German shepherd in American English
noun
one of a breed of large shepherd dogs having a coat ranging in color from gray to brindled, black-and-tan, or black, used esp. in police work and as a guide for blind people
Also called: German shepherd dog, German police dog
Word origin
[1930–35; shepherd prob. as trans. of G Schäferhund]