Having an unconventional, variable or asymmetric form.(adjective)
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Use "free-form" in a sentence
"As n|om fills their hearts, the clapping turns to a crisp cracking sound, and the singing of some of the best improvisers gives way to a kind of free-form, yodel-like scat singing that soars above the melodic line."
"You end up with a free-form piece and can later put several together to make something useful."
"A sleepover is free-form, and more fun than an afternoon playdate, he says."