thundering

A sailor's emphatic word for anything choice, large, fine, or powerful.

Thundering
·adj Emitting thunder. II. Thundering ·noun <<Thunder>>. III. Thundering ·adj Very great; — often...

Webster's Dictionary of the English Language
thundering
Very; exceedingly. A vulgar word used with pretty much the same latitude as the English devilish. I...

Dictionary of American Words And Phrases by John Russell Bartlett.