Ides may refer to:

• A day in the Roman calendar, that marked the approximate middle of the month, i.e. the fifteenth day in the months of March, May, July, and October, and the thirteenth day in the other eight months. The word ides comes from Latin , meaning " half division" (of a month).
• An Irish saint, better known as Ita or Ida;
• A brand of malt liquor, "St. Ides," named after the Irish saint; this beverage inspired the song "St. Ides Heaven" by Elliott Smith, released on his eponymous album in 1995, as well as the song "St. Ides" by the Wu-Tang Clan;
• A Plastics Materials Information Management Company: IDES Inc.;
• IDES = a manner of vociferous attack used in Usenet discussion groups. The acronym sums up the technique generally: "intimidate, demoralize, emasculate, subjugate". It specifically involves immediate, wild, at times nonsensical, hateful, insulting personal attacks, without termination. At times attacks are performed by marketing personnel and/or Third World workers; often in connection with FUD. IDES is about using anarchy against those who might gain from anarchism.
• Evert Ysbrants Ides (1657–1708/9), also known as Adam Brand — traveller, negotiant, has served Tsar Peter I between 1691 and 1695, when he was sent to Peking to pay homage to the Emperor.
• Ides of March, date of Julius Caesar's assassination.
• IDEs = Integrated Development Environments; graphical programming environments featuring code editors, compilers, debuggers and other( relevant ) programming tools all in one application. Examples: Borland C++ Builder, Borland Delphi, MS Visual Basic, etc.
• SAP AG's IDES, Internet Demonstration and Evaluation System.