Third-person singular simple present indicative form of countermand.(verb)
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Use "countermands" in a sentence
"How many commands/countermands can a real person take?"
"But exercise countermands some of the numbing effects of BMP, Dr. Kessler says."
"From this scene on, the story traces Jokla's desire for such an oracular judgement on her own part, the way that desire shades into an attempt to convince herself that it does apply, a hope that countermands suicidal fantasies:"