The definition of a piker is slang for a very frugal or extremely cautious person.
(noun)An example of a piker is a person who will only buy the cheapest of everything.
See piker in Webster's New World College Dictionary
noun
Origin: orig., prob. one from Pike County, Missouri, then applied to Missourians generally: reason for later uses obscure
Slang a person who does things in a petty or niggardly way; esp. one who gambles or speculates in an overly cautious waySee piker in American Heritage Dictionary 4
noun
Origin:
Origin: Possibly from Piker, a poor migrant to California
Origin: , after Pike County in eastern Missouri
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