Dalet (also spelled dāleth or Daleth) is the fourth letter of the Hebrew alphabet. In set theory, mathematicians originally intended to use daleth to represent the fourth transfinite cardinal numbers. The name "dalet" is connected to the word "delet", meaning "door". It also corresponds to the letter "delta" in the Greek alphabet.
- "Greek/Hebrew/Latin-based Symbols in Mathematics". Math Vault. 2020-03-20. Retrieved 2020-10-07.
- "DALET (ר) - JewishEncyclopedia.com". www.jewishencyclopedia.com. Retrieved 2020-10-07.