Major ref. Crossword Clue

 The answer to the crossword clue "Major ref." is OED.

The OED stands for Oxford English Dictionary. It is the most comprehensive and authoritative dictionary of the English language. It was first published in 1884 and has been expanded and updated many times since then.

The OED contains over 600,000 words and phrases, and it provides information on their meaning, origin, and usage. It is a valuable resource for anyone who wants to learn more about the English language.

Here are some other possible answers for the crossword clue "major ref.":

Merriam-Webster

Webster's

Cambridge Dictionary

Macmillan Dictionary

Collins Dictionary

American Heritage Dictionary

I hope this helps!