‘Up in arms’ started as a literal expression in the sixteenth century which became a more figurative idiomatic expression during the seventeenth century. This old cliche is still quite familiar today.
Meaning of being ‘Up in Arms’
To be up in arms means to be angrily protesting something in a quite public manner, or to be openly rebellious. When someone is up in arms, they are not only angry, but they are letting everyone know about it.

Usage
The expression ‘up in arms’ is usually followed by a phrase starting with over or about such as “The employees were up in arms over not being paid overtime wages.”
Examples Of Use
“Democrats are up in arms about the new health care bill.”
“Protestors, up in arms over the administration’s climate policies, gathered in front of the White House.”
Origin
When this expression first came to use, it meant to literally take up arms against a perceived enemy. For example, it appeared in Jonathan Swifts first major work, A Tale of a Tub, published in 1704: “All the men of wit and politeness were immediately up in arms through indignation.”
Usage
The expression ‘up in arms’ is usually followed by a phrase starting with over or about such as “The employees were up in arms over not being paid overtime wages.”
More Idioms Starting with U
More Arm Idioms
- Twist Someone’s Arm
- Armed to the Teeth
- Give Your Right Arm (for something)
- Arm and a Leg, an
- Babe in Arms, a
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