Twelfth, especially as the final one of a set of twelve.(adjective)
A twelfth.(noun)
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Use "dozenth" in a sentence
"The dragon swished its tail, and for the dozenth time that afternoon Yrung flew through the air."
"For the dozenth time, maritime law recognizes the right of a belligerent operating a blockade to seize blockade runners in international waters."
"Comedy Central is apparently coming out with a new series in which Jesus is presented as a regular guy for comedic effect for the dozenth time that I can recall off the top of my head."