To set (an automatic control, for example) beforehand: preset a microwave oven.
To set (a timing device) so that something begins to operate at the time specified
American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
A control, such as a variable resistor, that is not as accessible as the main controls and is used to set initial conditions
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