-cule suffix forming nouns indicating smallness: animalcule. [from Latin -culus, diminutive suffix; compare -cle]Collins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014-cle1 , a suffix of Latin diminutive nouns borrowed into English via French: used later in adaptations of words borrowed directly from Latin: article; conventicle; corpuscle; particle. [