keep clear

• stay awayRemain at distance
• avoidStay away from
• steer clearActively avoid something
• warningAlert about danger
• cautionCareful attention to risk

distance · barrier · hazard · do not enter · stand back · restricted · off-limits · danger · obstruction · clearance · no parking · emergency exit · fire lane · gap · space · unobstructed · passage · access

• road markingscenter line, centerline, lane line, double yellow, lane lines
• nautical signalssignal flag, signal flags, golf flag, semaphore, substitutes
• railway signscrossbuck, railroad crossing, level crossing, crossing sign, semaphore