The phrase "small nub" refers to a small, rounded, or protruding part of something. It usually describes something that is tiny or insignificant in size and doesn't stand out much. Full definition
These chew toys are naturally flavor - enhanced to encourage chewing, and small nubs make great dental cleaners as the clean teeth and massage your dog's gums. (caninejournal.com)
After a quiet week last week, I've been hard at work these last seven days wearing my thumbs down into small nubs. (heroesofhandheld.wordpress.com)
I scoop a small nub of butter into a 13x9» baking dish and have the kids work it all over the bottom and sides with their hands. (bonappetit.com)