IPA: /ˈlɪt.əl.ər/
KK: /ˈlɪtəlɚ/
Smaller in size or amount than something else.
The littler dog was much more playful than the bigger one.
Littler → It is formed from "little" (from Old English "lytel", meaning small) and the comparative suffix "-er" (meaning more). The word "littler" means more small or smaller than something else.
Think of 'little' as meaning small, and the '-er' indicates a comparison, so 'littler' means more small.