RMD stands for required minimum distribution. It's the minimum amount of money you're required to take out of your retirement plan once you turn 72, or 70 1/2 for years prior to 2020. Your 1099-R issuer is required to follow RMD rules and regulations, so if you received a distribution and you're at least 72 years young, you can be almost certain you received an RMD. However due to the Cares Act passed in response to the pandemic, required minimum distributions are suspended for the 2020 tax year.