uttermost [noun] [U]The children's endless demands tried her patience to the utmost.The new model of the car offers the utmost in power and performance.To do/try your utmost is to do something as well as you can by making a big effort.Each area felt it must do its utmost to make its part of the festival a success.She tried her utmost to finish in time.
UTMOST
Meaning of UTMOST in English
Cambridge English vocab. Кембриджский английский словарь. 2012