It stands for Old Kinderhook, the nickname of Martin Van Buren who came from Kinderhook, New York.

ok代表Old Kinderhook，这是一位来自纽约，金德虎克的名叫马丁•凡•布伦的人的绰号。

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The letters were taken from the name of the town where Martin Van Buren was born Old Kinderhook,New York.

VOA: special.2010.02.28

This week, Steve Ember and Gwen Outen talk about Martin Van Buren and the start of his presidency.

VOA: special.2009.01.01

Last week in our series, we talked about the election of Martin Van Buren in 1836 as the eighth president of the United States.

VOA: special.2009.01.01

And Martin Van Buren wanted to be Andrew Jackson, without some of Jackson's sharp edges.

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