Maloney: An uneven bar skill named after Kristen Maloney. She first performed it in international competition in the 1997 World Championships. It consists of a pike sole circle backward to handstand with a 360° turn after the handstand phase to mixed-L or L grip.  The skill has been rated by the FIG as a D level skill and the FIG number is 7.409.

Maloney: Another uneven bar skill named after Kristin Maloney. She first performed the skill internationally in the 1997 World Championships. The skill begins from an inner front support on the low bar and consists of a  pike sole circle backward through a handstand with flight to a hang on the high bar The skill has been rated by the FIG as a D level skill and the FIG number is 7.410.

Mat: A term that refers to the various types of covered soft polyurethane foam landing equipment. Mats are used for safety, dismount landings and for performing on. 

McCool: A balance beam mount named after Courtney McCool, who first performed the skill in international competition in  2004. The beam mount approaches toward the end of the beam and is a flyspring forward with flight before and after the hand support on the beam and lands on both feet - approach at end of beam. The skill has been rated by the FIG as a D level skill and the FIG number is 1.409.

McNamara: An uneven bar mount named after Julianne McNamara. She first performed the skill internationally in 1981. The mount is performed with a jump to hang on the high bar into a free hip circle to handstand with 1/2 turn in the handstand. The skill has been rated by the FIG as a D level skill and the FIG number is 1.415.

Melissanidis: A vaulting skill in which the gymnast performs a round-off entry onto the vault table and after blocking off the vault table, rotates a 2 ½ back somersault. It is named after the Greek gymnast, Melissanidis, who performed it first in international competition. 

Miller: An uneven bar skill named after Shannon Miller.  It consists of a cast to handstand, with a 1 ½  turn after the handstand to a mixed-L grip. The skill has been rated by the FIG as a D level skill and the FIG number is 2.401.

Miller: Another skill named for U. S. gymnast Shannon Miller, this one on the balance beam.  It consists of a  back dive with a quarter twist to a handstand, followed by a half pirouette.

Mixed Grip: On the bars, this term refers to a grip with one hand in regular grip and the other in reverse grip, which means on one hand the fingers are facing away and are facing in on the other hand finger.
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Mount: This term is used both to identify the first skill with which the gymnast starts a gymnastics routine and also means to get up onto a gymnastics apparatus. 
 

Gymnastics Dictionary