The French piece name merel
The word merel is the continuation of the Latin word marr(us), meaning stone or gaming piece. Consequently, the game name merelles meant literally "game with pieces".
In the Middle Ages, merel (or a variant like marelle or mereau) meant piece used by playing draughts, morris or hopscotch. In the 15th century the word became less common. Draughts players replaced the word merel by the word dame. Morris players followed, calling the morris piece also dame. Later the draughts players replaced the word dame by the word pion; the morris players did the same by mentioning the morris piece pion also. Hopscotch underwent another evolution; in current French the piece is called palet, sometimes also pierre.
The table below shows a parallel: the metaphors with the word merel became less frequent as soon as draughts was transferred to the chequered board and the game name merelles became less frequent. This proves that the metaphors were generated by draughts and not by morris.
The four great board games of the Middle Ages were tables, draughts, chess and morris. Tables had its own French name for the piece: table, and its own name for the board: tablier. Draughts had its own name for the draughts piece: merel and its own name for the draughts board: merellier. Chess had its own name for the chess piece: eschec and for the chess board: eschequier. And morris? There was neither a special word for the morris piece nor for the morris board, which raises the question whether morris did not have a low social status.
The above is based on Stoep 1997:179-181 and 2007:149-154.