Webster's Revised Unabridged Dictionary · 1913

Marl

Marl , transitive verb

[See Marline.]

(Nautical) To cover, as part of a rope, with marline, marking a peculiar hitch at each turn to prevent unwinding.
Collocations (1)
Marling spike (Nautical) , See under Marline.

Marl , noun

[Old French marle, French marne, Late Latin margila, dim. of Latin marga marl. Originally a Celtic word, according to Pliny, xvii. 7: “Quod genus terrae Galli et Britanni margam vocant.” r274.]

A mixed earthy substance, consisting of carbonate of lime, clay, and sand, in very variable proportions, and accordingly designated as calcareous, clayey, or sandy. See Greensand.
Quod genus terrae Galli et Britanni margam vocant.

Marl , transitive verb

[Compare French marner. See Marl, n.]

To overspread or manure with marl; as, to marl a field.