[verb ges-tuh-meyt; noun ges-tuh-mit, -meyt]Informal.
- to estimate without substantial basis in facts or statistics.
- an estimate arrived at by guesswork.
Origin of guesstimate
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
- an estimate calculated mainly or only by guesswork
- to form a guesstimate of
Word Origin and History for guesstimate
Online Etymology Dictionary, © 2010 Douglas Harper