tall order

Definition

A big job; a difficult challenge.

Etymology

tall (“big, large”) + order (“request”).

Example Sentences

• "[W]e must come, consequently, to the impressive conclusion that to live on potatoes alone[…], a man must eat at least 30 lbs. of potato a day—which would be rather a tall order, even for an Irishman."
• "Guess they'd find it a pretty tall order trying to interfere with an American citizen."
• "We suggest that your committee assume the responsibility for establishing a definite long range construction program for the American Merchant Marine. This is a tall order but one of extreme urgency. An entire indusry is now suspended in the balance between war and peace, and upon you and your committee depends which way the scales will tip."