A bringing together, as of livestock for counting.(noun)
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Use "mustering" in a sentence
"I have no problem with congratulating Obama for his success in mustering the delegates to become the presumptive nominee, but I don't think that people should criticize Hillary for not accepting defeat more immediately and more explicitly."
"Occasionally it happened, especially in mustering times, that nobody remembered to pen the goats in their yard by the lagoon, and on these occasions they would get under the house, and the noise of their horns knocking against the floor of her bedroom would so effectively destroy Lady Bridget's chances of sleep that she would rise in the night and drive them into their fold."
"One day was spent in mustering sheep, an employment not at all to Norah's taste."