- this sense?) (as imperative) To remove one's hat out of respect.
- this sense?) (as imperative, with to) To acknowledge the contribution of; to congratulate.
- Ellipsis of a form of take one's hat off to (Wiktionary)
“Like recruits to be mustered in we were aligned in one rank before the piazza, and with hats off and eyes to the front we stood ready for inspection, each in tremulous suspense for the issue; for, be it known, that to be a house-boy, to live in the "big house," to wait upon the master and the mistress, was the acme of a negro's ambition.”
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