1. noun An attempt to accomplish something in a short amount of time. Typically followed by "time" or "the clock." After getting a flat tire, it was a race against the clock to make it to the airport in time. It will be a race against time to get these donor kidneys to the hospital before the ice packs melt.

2. noun A competitive time or speed trial against someone or something Let's have a race against the two fastest runners and see who wins! Hey, wanna race against me? I bet I can win!

3. verb To compete in such a trial. He wants to race against my old mustang, convinced his souped-up new hotrod can compete! Hey, wanna race against me? I bet I can win!

4. verb To act very quickly or attempt to accomplish something in a short amount of time. Typically followed by "time" or "the clock." Jen's going to have to race against the clock if she wants to get her story in tomorrow's newspaper—it's almost time to send it to the publisher! The doctors are racing against time in their efforts to cure Mary's disease.