IPA: /ˈaʊtsoʊl/
KK: /aʊtsoʊl/
The bottom part of a shoe or boot that touches the ground.
The outsole of my new sneakers is made of rubber for better grip.
Outsole → It is formed from "out-" (meaning outside) and "sole" (from Old French *sole*, meaning the bottom part of a shoe). The word "outsole" refers to the outer bottom part of a shoe that comes into contact with the ground.
Think of the 'outside' ('out-') part of a shoe's 'bottom' ('sole') — that's what an outsole is.
No commonly confused words.