CDR stands for Call Detail Record, which is a telecommunications term used to refer to the details of a phone call, including the time and date, duration, caller ID, and more. As CDR refers to records of phone calls made, there aren't many antonyms that directly relate to it. However, some opposite or opposing words could be 'deletion' or 'erasure,' as it is the complete opposite of recording or keeping a record. Another possible antonym could be 'void,' meaning something that is empty or without substance, which, in the case of CDR, would refer to the absence of any data or records.