The term 'cousin of a weasel' can be described by two crossword solutions: SABLE (5 letters) and STOAT (5 letters). Sables are small mammals that belong to the marten family and are native to Russia, northern China, and Japan. They have thick fur that is typically brown or black in color. Stoats are also small mammals that belong to the weasel family and are native to Europe, Asia, and North America. They have a reddish-brown coat with a white underside and a black-tipped tail. Both sables and stoats are cousins of weasels and share many of the same characteristics.