Thingus

Placeholder names are names used as placeholder words, i.e., referring to things, places, or people, the names of which or of whom do not actually exist; are temporarily forgotten, or are unimportant; or in order to avoid stigmatization, or because they are unknowable or unpredictable given the context of their discussion; or to deliberately expunge direct use of the name. Placeholder names for people are often terms referring to an average person or a predicted persona of a typical user or for an individual whose name is unknown. Placeholder names serve as a "common language" that provide flexibility and clarity when talking or writing about concepts. Some morphologists "will distinguish between placeholders such as thingummy and placeholder names like John Doe". In computer programming and printing, placeholder names allow a creator to test or visualize the end product.

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