noun / adjective / verb
hobnail
HAHB-nayl/hˈɑbnˌeɪl/
A short, heavy nail used to reinforce a boot sole.
The loose hobnail has a short, thick shank for reinforcing the boot's sole.

Etymology
The first piece probably refers to a rounded peg or pin, paired with a metal nail. The compound names a short, thick, large-headed nail used in heavy boot soles.
More examples
- Several hobnails are missing from the heel of my boot.
- His hobnailed boots clatter across the stone floor.
- The shoemaker hobnails the soles to help them resist wear.
Forms
hobnail · hobnails · hobnailed · hobnailing