es ‧ ti ‧ ma ‧ tion AC /ˌestəˈmeɪʃ ə n, ˌestɪˈmeɪʃ ə n/ BrE AmE noun
[ Word Family: noun : ↑ estimate , ↑ estimation , ↑ estimator , ↑ overestimate ≠ ↑ underestimate ; verb : ↑ estimate , ↑ overestimate ≠ ↑ underestimate ; adjective : ↑ estimated ]
1 . [singular] a judgment or opinion about someone or something
in sb’s estimation
In your estimation, who’s going to win?
go up/come down in sb’s estimation (=be respected or admired more or less by someone)
2 . [countable] a calculation of the value, size, amount etc of something:
Estimations of total world sales are around the 50 million mark.