English
guesstimation
Blend of guess + estimation.
A blend of guess + estimation
Middle English gessen ‘to guess’
English guess
Latin aestimo ‘to determine the value of something’
Latin aestimatio ‘valuation, estimation according to its worth,…’
Old French estimacion
Middle English estimacioun
English estimation
Today it means
noun An estimation made without good justification and often biased.
Language periods are conventional ranges, not dates for this word.
Etymograph / guesstimation