Here are the possible solutions for sign of something clue
Answer
Clue
Relevancy
atop
Clue
Sign denoting that something is perched on something else?
Definition
on top of
omen
Clue
Good sign or bad sign
Definition
to provide with a prophetic sign
ptomaineconcourse
Clue
Warning sign at a train station's food court? (NOTE: The original sign, without my additions, actually exists. It's in Grand Central Terminal in NYC, on the lower level — the food court level. The sig