Bloodhound's Trail is a term used to describe the ability of a bloodhound to follow a SCENT. This ability is based on the bloodhound's keen sense of smell, which is so powerful that it can detect and follow a SCENT even after it has been washed away. The crossword solutions for this term are ODOR (4 letters) and SCENT (5 letters). ODOR and SCENT are both terms used to describe a smell, with ODOR being a more general term and SCENT referring to a specific smell.