The word "bider" can have several synonyms depending on the context in which it is used. It can refer to someone who participates in an auction, and in this case, some alternative words could include "bidder," "auction-goer," "offerer," or "proposer." On the other hand, in a literary sense, "bider" could be used to describe someone who waits patiently for a particular event or circumstance to occur, and in this case, synonyms could include "waiter," "expectant," "patient," or "anticipatory." Ultimately, the choice of synonym for "bider" will depend on the intended meaning and usage, as well as the particular style and tone of the writing.