color up

• colour up

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color up (third-person singular simple present colors up, present participle coloring up, simple past and past participle colored up)

1. To blush (to go red).
   • 1790, Jane Austen, “Jack and Alice”, in Juvenilia:

     Alice had already begun to colour up and was beginning to speak, when her Ladyship perceiving her displeasure, continued thus.

2. (poker) To exchange a high number of low-value chips (of one color) for a lower number of higher value (of a different color), but keeping the same overall value.