-cule

word-forming element used to make diminutives, from French -cule or directly from Latin -culus (masc.), -cula (fem.), -culum (neuter); these appear to be variants of the diminutive suffix -ulus (see -ule) used after -i-, -e-, -u-, and consonant stems [Gildersleeve], or might be a double-diminutive involving "an ancient diminutive suffix *-qo-" [Palmer, "The Latin Language"].

There also was a Latin instrumentive suffix -culo-, -culum in baculum "walking stick," gubernaculum "rudder, helm; management, government," operculum "cover, lid," obstaculum "a hindrance, obstacle," oraculum "divine announcement."