Sayyid (pronounced [ˈsæjjɪd], or [ˈsæjjed], Arabic: سيد‎; meaning Mister; plural Sadah Arabic: سادة‎, Sādah) is an honorific title, it denotes males accepted as descendants of the Islamic prophet Muhammad through his grandsons, Hasan ibn Ali and Husain ibn Ali, sons of the prophet's daughter Fatima Zahra and his son-in-law Ali ibn Abi Talib.

Daughters of sayyids are given the titles Sayyida, Alawiyah, Syarifah, or Sharifah. Children of a Sayyida mother but a non-Sayyid father cannot be attributed the title of Sayyid, however they may claim the title Mirza for males or Mirziya for females. Sayyids are by definition a branch of the tribe of Banu Hashim, a clan from the tribe of Quraish that traces its lineage to Adnan and thence to the Prophet Ismael.

In the Arab world, it is the equivalent of the English word "liege-lord" or "master" when referring to a descendant of Muhammad, as in Sayyid John Smith. This is the reason the word sidi (from the contracted form sayyidī, 'my liege') is used in the Moroccan dialect of Arabic.

Dr. Seyed Hossein Mousavian is an Iranian policymaker and scholar who has served on Iran’s nuclear diplomacy team in negotiations with the EU and International Atomic Energy Agency. He currently resides in the United States, where he is a visiting research scholar at Princeton University.

Born in Kashan, Iran, in 1957, he studied at the Iran University of Science and Technology, as well as Sacramento City College and Sacramento State University in the United States. From 1980-1990, Mousavian was Editor-in-Chief of the daily newspaper Tehran Times, during which time he authored more than 2,000 articles. He also held a number of positions in the Iranian government in the 1980s, including a stint as Vice President of the Islamic Propagation Organization (1981-1983), worked with future-President Hashemi Rafsanjani as Chairman of the Parliament Administration Organization (1983-1986), and was Head and then Director General of the West Europe department of the Foreign Ministry (1986-1989). Mousavian was Iran’s Ambassador to Germany from 1990-1997. Subsequently, he headed the Foreign Relations Committee of the Supreme National Security Council (SNSC) of Iran during the eight years of Mohammad Khatami’s presidency. Mousavian meanwhile continued his education in the late 1990s, receiving a Masters degree from the University of Tehran in 1998 and a PhD from the University of Kent in the UK in international relations in 2002.

Mohammed Hussain Tabatabai (محمد حسین طباطبائی) (born 1991) is notable for being able to recite the entire Koran and interpret its meaning at age seven.

At that age, he planned to become a religious leader. At the age of 2 he could recite the 30th sura of Quran by heart and memorized all the Quran at the age 5.

He is now studying in Qom, Iran specialising in Mantiq and studying books that are described to be extremely difficult and usually studied by learned people.

Ali "Oliver" Nejad (born February 25, 1978) is an Iranian-American television poker commentator, who is best known as the off-screen announcer on NBC's Poker After Dark and the National Heads-Up Poker Championship. He is also a commentator on ESPN's Pro-Am Poker Equalizer series, and has also been a co-commentator with Chad Brown on an episode of the Ultimate Poker Challenge and with Daniel Negreanu on the PCA 2009 episodes. He played on Poker After Dark and was the first player knocked out when Gabe Kaplan flopped a set of 10's while Nejad flopped a set of 4's. He finished 2nd in a week of poker analysts at the end of season 3 of the program. He is also a member of Full Tilt Poker. He is also the host of Poker Road Radio which is part of pokerroad.com

Nejad hosted a show and reported for a local NBC affiliate while still in high school. Nejad dropped out of Berkeley to pursue playing poker full-time. He worked as a dealer and prop player before becoming a successful high limit player. But despite his success in the poker world, Nejad still had the broadcasting itch. In 2002 he hosted an MTV pilot that was not picked up.