Meaning of BIDDER in English
/ ˈbɪdə(r); NAmE / noun
a person or group that offers to pay an amount of money to buy sth :
It went to the highest bidder (= the person who offered the most money) .
a person or group that offers to do sth or to provide sth for a particular amount of money, in competition with others :
There were six bidders for the catering contract.
Oxford Advanced Learner's English Dictionary. Оксфордский английский словарь для изучающик язык на продвинутом уровне. 2005