Overly fancy with little function; newfangled; complicated(adjective)
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Use "fancy-pants" in a sentence
"Two decades ago, she moved to Massachusetts to become what she called a "fancy-pants professor at Harvard.""
"Really, dishes kind of stink too, especially after cooking fancy-pants dinners that require lots of pots and pans."
"Without a hint of an accent, and carrying himself like a cultured city-boy, Jesse, a supposed farm worker-cum-grocery clerk, seems to have an endless supply of cash in his wallet (chained to his belt, natch), not to mention a fancy-pants camera (which might have also benefited from being chained down – it disappears during the story)."