We found one dictionary that defines the word keep his nose to the grindstone:

General (1 matching dictionary)

1. keep his nose to the grindstone: Merriam-Webster

▸ Words similar to keep his nose to the grindstone ▸ Usage examples for keep his nose to the grindstone ▸ Idioms related to keep his nose to the grindstone ▸ Wikipedia articles (New!) ▸ Words that often appear near keep his nose to the grindstone ▸ Rhymes of keep his nose to the grindstone ▸ Invented words related to keep his nose to the grindstone