from
The Collaborative International Dictionary of English v.0.48
Calk \Calk\ (k[add]k), v. t. [imp. & p. p. {Calked}; p. pr. &
vb. n. {Calking}.] [Either corrupted fr. F. calfater (cf. Pg.
calafetar, Sp. calafetear), fr. Ar. qalafa to fill up
crevices with the fibers of palm tree or moss; or fr. OE.
cauken to tred, through the French fr. L. calcare, fr. calx
heel. Cf. {Calk} to copy, Inculcate.]
1. To drive tarred oakum into the seams between the planks of
(a ship, boat, etc.), to prevent leaking. The calking is
completed by smearing the seams with melted pitch.
[1913 Webster]
2. To make an indentation in the edge of a metal plate, as
along a seam in a steam boiler or an iron ship, to force
the edge of the upper plate hard against the lower and so
fill the crevice.
[1913 Webster]