F.O.S.

or f.o.s.

free on station.

free on steamer.

Slang: Vulgar. full of shit.

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for fos

There Fos arrived and conveyed them to the Castle of Hammershuus.
Memoirs of Leonora Christina|Leonora Christina Ulfeldt
Fos leapt into the air like an enraged animal, and said that she lied like a ——, &c.
Memoirs of Leonora Christina|Leonora Christina Ulfeldt
Fos was enraged at this, and would not remain, nor would he speak a word to our lady, who begged him to hear her.
Memoirs of Leonora Christina|Leonora Christina Ulfeldt
Her husband stated in his reply that Fos had taken his letters, and that in a rude manner.
Memoirs of Leonora Christina|Leonora Christina Ulfeldt

Fos was still at the castle; it is easy to believe that he was in great rage.
Memoirs of Leonora Christina|Leonora Christina Ulfeldt

British Dictionary definitions for fos

FOS

abbreviation for

fructooligosaccharide: a chain polymer of fructose found in a variety of plants, vegetables, and fruits and used as a sweetener

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012