Unposted is a term used to describe something that has not been communicated or shared publicly. Synonyms for unposted include unshared, unpublished, unannounced, unadvertised, and unspread. Unshared implies that something has been kept private or hidden from others. Unpublished suggests that something has not been formally released or made public in writing. Unannounced describes something that has not been announced or made known in advance. Unadvertised suggests something has not been promoted or marketed to the general public. Finally, unspread indicates that something has not been dispersed or made widely known. These synonyms can be used interchangeably to convey the same meaning as unposted.