Mab - A harlot.
Mad as a March Hare - Very angry.
Mad as a Hornet - Very mad.
Madder than an Old Wet Hen - Very angry. "Mama woke up madder than an old wet hen."
Made His Jack - Got what he aimed at.
Maggot - Derogatory term for sheep.
Mail-Order Cowboy - This was a derogatory term used to chide tenderfoot, urban "cowboys" who arrived from the East all decked out in fancy but hardly practical Western garb.
May Hay - To put in disorder, to make
Hay While the Sun Shines - To make the most of the day, or an opportunity.
A derogatory name for sheep was maggot, photo 1916 by Lewis Wickes Hine.
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