If something is traceable, it can be tracked or detected — like an email address or evidence of a crime.
The word traceable is just the adjective form of the common verb trace, meaning “to find.” So if you describe something as traceable, that just means that it can be detected. A poison that can be discovered in the body of a murder victim, for example, is a traceable poison. The word can also be used in the sense of something that can be tracked, such as a suspicious money transaction that’s traceable to your bank account. If something is traceable, it has left you a trail to follow it.
