a first, typical or preliminary model of something, especially a machine, from which other forms are developed or copied.
1.done, made, or happening only once and not repeated.“one-off tax deductible donations to charity”
noun: one-off; plural noun: one-offs
1.something done, made, or happening only once, not as part of a regular sequence.“the meeting is a one-off”
a person who is unusual or unique, especially in an admirable way.“he’s a one-off, no one else has his skills”