Annuity on the last survivor refers to a financial arrangement where a fixed sum of money is provided to individuals throughout their lifetime, with payments continuing until the last surviving person passes away. While there may not be widely recognized synonyms for this specific term, it can be described as a joint life annuity, survivorship annuity, or joint life insurance policy. Such arrangements offer financial security for couples or beneficiaries who require lifelong income protection. By understanding the varying terms and options available, individuals can make informed decisions when it comes to securing their financial future.