different between zonetime vs onetime

English

zone +? time

zonetime (countable and uncountable, plural zonetimes)

(rare) The time in a particular time zone, based on a meridian, as opposed to standard time.
- 2011, Lawrence Rick, Life is a Cruise: The Log of Done Dreamin' (page 83)
  For all our weather and radio reports, we use UTC or Greenwich, and for everything else we use zonetime. This is quite easy to find by taking your longitude and dividing it by fifteen. Subtract this number from UTC time and you have zonetime.

one +? time

onetime (not comparable)

Alternative form of one-time (“former; past”)
- 2004, The 9-11 Commission, 9/11 Commission Report, Chapter 4:
  A onetime special […] forces officer, he had worked with Albright when she was ambassador to the United Nations and had served on the NSC staff with Clarke.
Alternative form of one-time (“occurring once”)
- 2004, The 9-11 Commission, 9/11 Commission Report, Chapter 6:
  The additional funds included the FBI’s support of the 2002 Winter Olympics in Salt Lake City, Utah (a onetime increase) […]

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