Definitions for placeholderˈpleɪsˌhoʊl dər
Random House Webster's College Dictionary
a symbol in a mathematical or logical expression that may be replaced by the name of any element of the set.
Category: Common Vocabulary, Math, Philosphy
proxy, placeholder, procurator(noun)
a person authorized to act for another
a symbol in a logical or mathematical expression that can be replaced by the name of any member of specified set
Something used or included temporarily or as a substitute for something that is not known or must remain generic; that which holds, denotes or reserves a place for something to come later.
This is placeholder data, so youu2019ll want to include the real numbers as soon as you have them.