Wiktionary
adv. for a long time
Usage examples of "long-since".
There were ten of the beautiful bonds of the Great Lakes and Canadian Southern Railroad Company with their miniature locomotives and fields of wheat, and ten equally lovely bits of engraving belonging to the long-since defunct Bluff Creek and Iowa Central, ten more superb lithographs issued by the Mohawk and Housatonic in 1867 and paid off in 1882, and a variety of gorgeous chromos of Indians and buffaloes, and of factories and steamships spouting clouds of soft-coal smoke.
As whalemen from New Bedford, New London, and Sag Harbor opened up new whaling grounds in the North Pacific, Nantucketers stuck stubbornly to the long-since depleted grounds that had served them so well in past decades.
He was aware of ghost tingles in long-since lost magnetohydrodynamic limb and was tortured by an unassuageable, systemic hunger for a fluid environment.