Definition of -let suffix from the Oxford Advanced Learner's Dictionary

(in nouns) small; not very important booklet piglet starlet More Like This Suffixes -able, -age, -al, -ance, -ant, -arian, -ary, -dom, -ee, -er, -ese, -esque, -ess, -fold, -ful, -hood, -ify, -ion, -ish, -ism, -ist, -ista, -ite, -itis, -ize, -less, -let, -ling, -ly, -ment, -most, -ness, -oid, -or, -ous, -shipSee worksheet. Word Originoriginally corresponding to French -ette added to nouns ending in -el.
See the Oxford Advanced American Dictionary entry: -let