Definitions of trail:

• noun:   a path or track roughly blazed through wild or hilly country
• noun:   a track or mark left by something that has passed

  Example: "There as a trail of blood"

• noun:   evidence pointing to a possible solution

  Example: "The trail led straight to the perpetrator"

• verb:   move, proceed, or walk draggingly pr slowly

  Example: "John trailed behind behis class mates"

• verb:   drag loosely along a surface; allow to sweep the ground

  Example: "The toddler was trailing his pants"

• verb:   hang down so as to drag along the ground

  Example: "The bride's veiled trailed along the ground"

• verb:   to lag or linger behind
• verb:   go after with the intent to catch
• name:  A surname (rare: 1 in 100000 families; popularity rank in the U.S.: #8609)