mat (n.1)
loosely joined natural materials used as bedding, etc., Old English matte, from Late Latin matta "mat made of rushes" (4c.), probably from Punic or Phoenician matta (compare Hebrew mittah "bed, couch"). Meaning "tangled mass" is from 1835. That of "piece of padded flooring used in gymnastics or wrestling" is attested from 1892; hence figurative phrase go to the mat "do battle" (1910). The Latin word also is the source of German Matte, matze; Dutch mat, Italian matta. French natte "mat, matting" is from Late Latin secondary form natta (compare napkin).
mat (adj.)
1640s, "lusterless, dull" (of a color or surface), from French mat "dull, dead surface," from Old French mat "beaten down, withered, afflicted, dejected; dull," which is perhaps from Latin mattus "maudlin with drink," from madere "to be wet or sodden, be drunk," from PIE root *mad- "to be wet, drip" (see mast (n.2)). Or the French word might represent a transferred use from chess of mater "to checkmate, defeat," from Arabic (see mate (v.2)).
mat (n.2)
"sheet of backing material," 1845, from French mat "dull surface or finish" (15c.), noun use of Old French mat (adj.); see mat (adj.).
mat (v.)
early 15c., "to make mats," from mat (n.1). From 1540s as "to provide with mats, to cover with mats;" meaning "to become tangled" is from 1570s. Related: Matted; matting.