A loud vocalization made in response to or to oppose another shout, or shouting as a counter-tactic.
From counter- + shout (from Middle Dutch schout, magistrate, but influenced by loud calling). Likely a colloquial or poetic term.
In nature, countershout happens in animal communication—howler monkeys in the Amazon engage in 'countershout duels' where groups rival each other with increasingly loud calls.
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