"For bit" is an expression that means a short period of time. Some synonyms for "for bit" are "momentarily," "briefly," "temporarily," "fleetingly," and "shortly." These words all suggest a temporary lapse of time that is not long-lasting. Other synonyms could be "in a flash," "in an instant," "momentarily," or "in a jiffy." These words communicate that the activity or event is not meant to last for a long time and can be accomplished quickly. Whatever word you choose, the meaning is clear - this is something that will happen quickly, without much delay or hesitation.