Bobtail and Shepherd dog

Bobtail noun - Large sheepdog with a profuse shaggy bluish-grey-and-white coat and short tail; believed to trace back to the Roman occupation of Britain.

Shepherd dog and bobtail are semantically related. In some cases you can use "Shepherd dog" instead a noun "Bobtail".

Shepherd dog noun - Any of various usually long-haired breeds of dog reared to herd and guard sheep.

Bobtail and shepherd dog are semantically related. Sometimes you can replace term "Bobtail" with "Shepherd dog", this terms are similar.