[verb] [T] [past:] beseeched or besought [formal] - to ask for something in a needy and anxious way; begThey beseeched her not to climb the mountain that day, but she wouldn't listen. [+ object + to infinitive]Stay a little longer, I beseech you!
BESEECH
Meaning of BESEECH in English
Cambridge English vocab. Кембриджский английский словарь. 2012