(Saxon, of; Latin, ab, from, away). The house is a mile off —i.e. is “away” or “from” us a mile. The word preceding off defines its scope. To be “well off” is to be away or on the way towards well-being; to be badly off is to be away or on the way to the bad. In many cases “off” is part of a compound verb, as to cut-off (away), to peel-off, to march-off, to tear-off, to take-off, to get-off, etc. The off-side of horses when in pairs is that to the right hand of the coachman, the horses on his left-hand side are called the “near” horses. This, which seems rather anomalous, arises from the fact that all teamsters walk beside their teams on the left side, so that the horses on the left side are near him, and those on the right side are farther off.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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