Maj may refer to:

• Major, a rank of commissioned officer in many military forces
• Máj, a romantic Czech poem by Karel Hynek Mácha
• Máj (literary almanac), a Czech literary almanac published in 1858
• Marshall Islands International Airport
• MAJ or mis à jour - French expression meaning "revision date"

Máj (archaic Czech for the month May; ) is a romantic poem by Karel Hynek Mácha in four cantos. It was fiercely criticized when first published, but since then has gained the status of one of the most prominent works of Czech literature; in Czech, the poem now is memorized by schoolchildren and continuously in print.

Major is a military rank of commissioned officer, with corresponding ranks existing in many military forces. When used unhyphenated, in conjunction with no other indicators, the rank is just senior to that of an army captain and right below the rank of lieutenant colonel. It is considered the most junior of the field officer ranks.

Major is a sports manga series by Takuya Mitsuda. It has been serialized in Shonen Sunday and has been collected in 78 tankobon volumes. In 1996, it received the Shogakukan Manga Award for shonen.

Marshall Islands International Airport , also known as Amata Kabua International Airport, is located in the western part of Rairok on the south side of Majuro Atoll, the capital of the Republic of the Marshall Islands. The airport was built during World War II (1943) on Anenelibw and Lokojbar islets. It replaced Majuro Airfield, a coral-surfaced airstrip at Delap Island near the eastern end of Majuro Atoll that had been originally constructed by Japanese occupation forces in 1942.