A half-pay Major of Marines

I just read a Sherlock Holmes story in which a man was described as "a half-pay Major of Marines". Does that mean he retired early from the Marines, and so took a half pension rather than a full pension? I am planning on reading the story aloud to my 9-year-old, and I'd like to be able to explain what that means. Thanks for any confirmation anyone can provide.

Some military people, if placed on standby because of little need for them, eg a ship's captain with no current ship, would, in the old days, be put on half pay. I'm not sure whether this was still so in Holmes' time, but it's a possibility, especially for a Marine.

Julia went there at Chrustmas two years ago, and met there a half-pay Major of Marines, to whom she became engaged. ["The Adventure of the Speckled Band"]
half-pay. The reduced pay of an army or navy officer when he is not on active service.
From _The Annotated Sherlock Holmes_ by William S. Baring-Gould
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The Dutch having called in their fleete and paid their men half-pay. (Pepys, _Diary_, Nov 30, 1664)
Half-pay captains and half-witted beaux. (Somerville, _Poems_, 1727)
The half-pays have come over in great force. (_Pall Mall_, Aug 21, 1865)