Music

• Ma (Anjan Dutt album) (1998)
• Ma (Rare Earth album) (1973)
• Ma (Sagarika album) (1998)
• Ma (Zubeen Garg album) (2019)
• Ma! (He's Making Eyes at Me) , 1974 debut album of Scottish singer Lena Zavaroni
• Massive Attack, a British trip hop band
• In music instructions, "but", especially in the phrase ma non troppo (see Glossary of musical terminology#M)
• In tonic sol-fa, a flattened me
• Encyclopaedia Metallum: The Metal Archives, a website devoted to heavy metal bands
• Mā (musician), New Zealand songwriter and rapper

Fictional characters

• Ma (The Lion King), a main character in the animated film Lion King 1½
• Ma Beagle, in the Donald Duck universe
• Ma Hunkel, a DC Comics character
• Ma Kettle, a 1940s and 1950s comic film character
• The protagonist of Ma Perkins , an American radio soap opera which aired from 1932 to 1960
• The Ma family, in the 2014 South Korean television series 4 Legendary Witches

Other uses in arts and entertainment

• Ma (2019 film), a horror film starring Octavia Spencer and Luke Evans
• Ma (negative space), a word of Japanese origin used in art and design
• Memory Alpha, a Star Trek-oriented wiki
• Miss America, a beauty pageant, and the title awarded at said pageant
• MA (journal), a Hungarian art magazine

Chemistry

• Methyl anthranilate, used as a bird repellent
• Minor actinides, the actinide elements in used nuclear fuel other than uranium and plutonium
• Monomethyl aniline, a solvent, chemical intermediate, and gasoline additive
• Methylammonium (CH₃NH₃), e.g., in methylammonium lead halides

• Mesaconitine a potent cardiotoxin and neurotoxin from plants of the genus Aconite

Health and medicine

• MA (chemotherapy) is an acronym for Mitoxantrone + standard-dose Ara-C (cytarabine) chemotherapy regimen
• Marijuana Anonymous, a group recovery program aimed at marijuana addiction
• Marketing authorisation, an authorisation granted by a regulatory authority to market a new drug
• Medical assistant, a type of health care worker
• Metabolic acidosis, a medical condition in which the pH of body is decreased beyond the normal range
• Metabolic alkalosis, a medical condition in which the pH of body is elevated beyond the normal range
• Methamphetamine, a psychostimulant

Mathematics

• MA (complexity), a set of decision problems that can be decided by an Arthur–Merlin protocol
• Martin's axiom, an axiom in mathematical logic
• Moving-average model (MA), in statistics

Measurements

• Mach number (Ma), a measure of speed compared to the speed of sound
• Megaampere (MA), a multiple of the SI unit of electric current, the ampere
• Megaannum (Ma), one million years
• Milliampere (mA), a multiple of the SI unit of electric current, the ampere
• Myr, Mya, or Ma, meaning "million years ago"; (NB: broadly equivalent to "Megaannum (Ma)", see above)

Other uses in science and technology

• Mechanical advantage (MA), mechanical multiplier of input force
• Mechanical alloying (MA), a technique to produce alloys
• Marketing automation (MA), technology designed to automate marketing-related tasks
• Ma, a type of interface in an IP Multimedia Subsystem
• Ford MA, a 2002 concept car
• Nissan MA engine, an automotive engine introduced in 1982