Shaky or infirm, as with age; decrepit: creaky knee joints; a creaky regime. (adjective)
American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Use "creaky" in a sentence
"Instead it came first in creaky agricultural countries, and never did come where he expected it."
"Bumper car and Ferris wheel rides can charitably be described as "creaky.""
"However, I've also been pondering today on the possibility that the voicing here also involves laryngealization aka creaky voicing1."