1MacquevilleGermanic name, Maculf + villaGallo-Roman rural estate
2MaransLatin name *marentius + -acumThis ancient port on the bay of the Pictones at the confluence of the Sèvre Niortaise and the Vendée was destroyed by the Vikings in 830.
3MarennesLatin Maritima, village by the seaOn the Seudre estuary, opposite Oléron. Like Arvert, on the other side of the estuary, Marennes was once an island in the marshes. Ausonius reported that oysters were cultivated in the estuary of the Seudre .
4MarignacLatin name Marinius with -acum 
5MarsaisLatin name Marcius with -acum 
6Marsilly  
7MassacLatin name Macius with -acum 
8MathaMatta, bushes 
9MathesMata, bushesChalk hill in the marshes of Saint-Augustin and Bréjat, in Arvert.
10MazerayMaceracum, from Macerius Gallo-Roman name, nickname meaning 'thin' + -acumMacer his place
11MazerollesLatin maceriae, ruins with -olaLittle ruins (from the Roman period)
12MedisLatin meta, marker or hillBoundary marker ?
13MerignacLatin name Matrinius with -acum 
14Meschers-sur-Gironde  
15MessacLatin name Metius with -acum 
16MeursacLatin name Mursius with -acum 
17Meux  
18Migre  
19Migron  
20MirambeauOld Provencale mirer + Old French bel, see well, a vantage point 
21MoezeGallo-Roman name *Mogetius with -acumThe peninsula marks the northern extremity of the marshes of Brouage.
22MoingsOn the river Moingt (modonio) 
23MonsLatin mons, hill 
24MontendreMons Andronis, German name AndarGallo-Roman “castrum”
25MontguyonMontis Gwidonis, German name Wido 
26Montils  
27Montlieu-la-Garde  
28Montpellier-de-MedillanMontis + pastellLatin, hill + woad plant
29Montroy  
30Moragne  
31Mornac-sur-SeudreFrom morn (eminence) or from a corruption of "morne agne" (morte eau), mortlake. 
32Mortagne-sur-Gironde Remains of a Gallo-Roman spa at Vieille-Mortagne
33Mortiers  
34Mosnac  
35Mung  
36Muron On the great marsh of Rochefort.