thirds = 'a third helping of food'

[Jonathan Lighter]

OED has the less gluttonous "seconds" to 1792, but nothing again till 1918.
 Odd.

1918 _The Recruit: A Pictorial Naval Magazine_  (Sept.) 7: "Seconds" and
"thirds" are always available to the bluejacket with the double-barrel
appetite.

JL

--
"If the truth is half as bad as I think it is, you can't handle the truth."

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