Tra"cer (?), n. One who, or that which, traces.

Trac"er (?), n. 1. A person engaged (esp. in the express or railway service) in tracing, or searching out, missing articles, as packages or freight cars.

2. An inquiry sent out (esp. in transportation service) for a missing article, as a letter or an express package.

Tra"cer (?), n. One who, or that which, traces.

Trac"er (?), n. 1. A person engaged (esp. in the express or railway service) in tracing, or searching out, missing articles, as packages or freight cars.

2. An inquiry sent out (esp. in transportation service) for a missing article, as a letter or an express package.

• (chemistry) A chemical used to track the progress or history of a natural process.
  
• A piece of ammunition for a firearm that contains magnesium or another flammable substance arranged such that it will burn and produce a visible trail when fired at night.
  
• The act of tracking or investigating something.
  
• A person who traces something.
  
  French
• to draw (a diagram), to trace out