This is the 42nd most frequent Lithuanian word.
m
The Lithuanian letter "m" itself is not a standalone word but a letter in the alphabet; if used as an abbreviation, its meaning depends on the context (e.g., "metų" for "years").
'Marios' is used to describe a large body of water; 'marias' (with 'm') follows declension rules for the location.
Miestas netoli marios yra nuostabus.
The city near the lagoon is wonderful.
'M' mimics the start of a sound (murk) in animal imitation, introducing the phrase.
Ar girdi, kaip murkia katė?
Can you hear the cat purring?
'm' is used as shorthand for 'mathematiką' as a casual abbreviation.