Bifold means folded twice or in half. The antonyms for this word are unfolded or unfurled which means to spread out and straighten. Another antonym for bifold is single, which means without another one or unaccompanied. Further, the antonym of bifold can also be expanded which means to increase in size, extent, or quantity. The opposite of bifold can also be multiplex or manifold which are used to refer to many or various forms. Thus, depending on the context, several antonyms such as unfolded, single, expanded, multiplex, or manifold can be used to describe the opposite of bifold.