Malevolent: having or showing a wish to do evil to others.
Malignant: malevolent.

Malinger: exaggerate or feign illness in order to escape duty or work. (Proust. all the outcry was mere malingering)

Mansuetude: meekness; gentleness. (Proust, ‘he exhibits on occasion a critical m* that is not easily explicable.)
Manumit: release from slavery; set free. (Proust, a m* of tears)

Mawkish: sentimental in a feeble or sickly way. (Proust)

Mete: dispense or allot justice, a punishment, or harsh treatment.
Misanthrope: a person who dislikes humankind and avoids human society.
Molder/Moulder: slowly decay or disintegrate esp. bc of neglect.
Moribund: (of a person) at the point of death. (of a thing) in terminal decline; lacking vitality.
Morphology: the study of the forms of things, in particular: biology, linguistics.
Motive: (adj) 1. Producing physical or mechanical motion. 2. Causing or being the reason for something.
Multivalency: Multivalent: 1. Having or susceptible to many applications; interpretations, meanings, or values. “the multivalency of Lorca’s images”