We found 3 dictionaries that define the word main yards:

General (3 matching dictionaries)

1. main yards: Merriam-Webster
2. main yards: Collins English Dictionary
3. main yards: Vocabulary.com

(Note: See main_yard as well.)

Definitions from WordNet (main yard) ▸ noun:  yard for a square mainsail ▸ Also see main_yard ▸ Words similar to main yards ▸ Usage examples for main yards ▸ Idioms related to main yards ▸ Wikipedia articles (New!) ▸ Words that often appear near main yards ▸ Rhymes of main yards ▸ Invented words related to main yards