II

II is the Roman numeral for 2.

II may also refer to:

Biology and medicine

• Image intensifier, medical imaging equipment
• Invariant chain, a polypeptide involved in the formation and transport of MHC class II protein
• Optic nerve, the second cranial nerve

Economics

• Income inequality, or the wealth gap, in economics
• Institutional Investor (magazine), an American finance magazine

Music

• Supertonic, in music
• ii, a 2018 song by CHVRCHES

Albums

• II (2 Unlimited album), 1998
• II (Aquilo album), 2018
• II (Bad Books album), 2012
• II (Boyz II Men album), 1994
• II (Capital Kings album), 2015
• II (Charade album), 2004
• II (The Common Linnets album), 2015
• II (Compact Disco album), 2011
• II (Cursed album), 2005
• II (Espers album), 2006
• II (Fuzz album), 2015
• II (Hardline album), 2002
• II (High Rise album), 1986
• II (Khun Narin album), 2016
• II (Kingston Wall album), 1993
• II (The Kinleys album), 2000
• II (Kurious album), 2009
• II (Last in Line album), 2019
• II (Lords of Black album), 2016
• II (Maylene and the Sons of Disaster album), 2007
• II (METZ album), 2015
• II (Moderat album), 2013
• II (The Presidents of the United States of America album), 1996
• II (Sahg album), 2008
• II (Seven Thorns album), 2013
• II (Unknown Mortal Orchestra album), 2013
• II (Xerath album), 2011
• II, by Krux, 2006
• II, by Majical Cloudz, 2011
• II, by Viva Brother, 2017
• II, an EP by TNGHT, 2019
• Crystal Castles II, 2010
• Led Zeppelin II, 1969
• Meat Puppets II, 1984
• Soul Assassins II, 2000
• Viva Koenji!, Koenji Hyakkei album, also known as 弐(II)
• Iris II, by Iris, 1987

People and social groups

• Ii is a Japanese surname, daimyō of Hikone:
  • Ii clan, Japanese clan (Sengoku period)
  • Ii Naomasa, one of four Guardians of the Tokugawa clan
  • Ii Naotora, female daimyō and foster mother of Naomasa
  • Ii Naoyuki, a Japanese author
• II, drummer for the band Sleep Token
• John Papa ʻĪʻī, a Hawaiian noble

Other uses

• ii (digraph), a digraph in certain romanized alphabets
• ii (IRC client), short for IRC It, an Internet Relay Chat client for Unix-like operating systems
• Ii, Finland, a municipality of Finland
• Illegal immigrant (especially in Hong Kong and Macau vernacular)
• Index Islamicus, a bibliography database of publications about Islam and the Muslim world
• Internet Infidels, a discussion forum
• IBC Airways (IATA code: II)
• Yi language (ISO 639-1: ii)