MARTINI is a coarse-grained force field developed by Marrink and coworkers at the University of Groningen, initially developed in 2004 for molecular dynamics simulation of lipids, later (2007) extended to various other molecules. The force field applies a mapping of four heavy atoms to one CG interaction site and is parametrized with the aim of reproducing thermodynamic properties.

Martini may refer to:

• Martini (cocktail), a popular cocktail
• Martini (vermouth), a brand of vermouth
• Martini (surname)
• Martini (automobile company), a Swiss automobile company
• Martini (quartet), the 2012 Sweet Adelines International champion quartet
• MARTINI, a molecular dynamics force field in chemistry
• Martini Cars, a French manufacturer of racing cars
• Martini Racing, motor racing teams sponsored by Martini & Rossi
• Martini, a Latvian holiday

Martini or Martindiena is an ancient Latvian winter welcoming holiday, when the time of piegula and shepherding came to an end. According to a solar calendar, Martindiena marks the midpoint between the autumnal equinox (Mikeli) and winter solstice (Ziemassvetki), and is celebrated in the middle of November. Martini ended Velu laiks (Time of the Dead) and started Ledus laiks (Time of Ice), when the swamp became passable and raids of armed men sitting on horses were expected.