overestimation has definitions from the fields of mathematics,psychology,writing
1
[ noun ] (writing) an appraisal that is too high

Used in print

(Clifford H. Pope, The Giant Snakes....)

It is often stated that the largest snakes require five years to attain maturity , but this apparently is an overestimation .

2
[ noun ] (mathematics,psychology) a calculation that results in an estimate that is too high

Related terms

estimate overestimate

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