Meso or mesos may refer to:

• Apache Mesos, a computer clustering management platform
• Meso, in-game currency for the massively multiplayer online role-playing game MapleStory
• Meso compound, a stereochemical classification in chemistry
• Mesolithic, archaeological period between the Upper Paleolithic and the Neolithic
• Mesopotamia, the first major river civilization, known today as Iraq
• Mesoamerica, Americas, or Native Americans
• Mesothelioma, a form of cancer
• Mesoscopic physics, subdiscipline of condensed matter physics that deals with materials of an intermediate size
• Multiple Equivalent Simultaneous Offers, a strategy used in negotiation