The specific combination of lights, colors, or semaphore blade positions displayed by a signal to convey a rule to the train crew. While the indication is the actual rule the crew must obey, this term refers strictly to what the signal looks like physically, such as a solid red light, a flashing yellow over green, or a horizontal blade.
Heard on the job
We caught a restricting aspect at the west end of the siding and had to crawl the rest of the way in.
Insider tip
Rookies often confuse aspect (what you see) with indication (what you do). You call out the aspect, but you obey the indication.
Do not mix it up with
- Signal aspect: Signal aspect is the full formal term, but crews on the radio almost exclusively just say aspect.