A traffic light, between the green light and the red light, indicating that vehicles may proceed with caution.(noun)
Limited approval or permission to proceed.(noun)
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Use "yellow light" in a sentence
"The night had risen up to all but full dark now, and he could see off on a hillside that there seemed to be a yellow light moving wavery and inconclusive through the trees, one moment haloed and diffuse, the next a hard bright point."
"Below the tree, a rectangle of yellow light from the kitchen window stretched out along the ground to touch the live oak's trunk."
"She was peering into the dark shadows of the station, the only light on her the backglow from the pale yellow light in the airlock behind them, and beyond that the distant light from their travel pod."