(chemistry) A repeat unit: a structural unit which through repetition forms a polymer.

(fantasy) merpeople

(obsolete) Alternative form of mayor and mair.

(chemistry) Used to form words relating to chemical structure, denoting parts of a molecule, for example, monomer (one part), dimer (two parts), polymer (many parts).

sea; marine; applied to beings that are fully or partly sea-creatures.

(fantasy) Of, pertaining to, or associated with the realm of mermaids and mermen.

Alternative form of mero- (“part, partial”) used before a vowel

(space science, US, NASA) Initialism of Mars Exploration Rover.

plural of mer

(medicine) Acronym of Middle East respiratory syndrome; also Mers. / (loosely) Middle East respiratory syndrome coronavirus