Having a size of the order of a millimeter(adjective)
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Use "millimetric" in a sentence
"Bodies based on Truchet's system appear to have been used throughout the 18th century by the Imprimerie royale, until a 'millimetric' point of 0.4 mm was introduced at the Imprimerie impériale in about 1810 by Firmin Didot."
"His single carefully greased kiss-curl flipped over then whipped back with millimetric precision to its position above DeMarco's right eye."
"You don't use them for wingshooting, especially the millimetric bores-- you use them from blinds, over decoys, at ranges under 10 yards, to shoot small legal birds FOR FOOD."