What is the meaning and derivation of 'cowp'?

The verb and noun in the meaning of "to tip / a tip" seems to have developed from the French coup/ couper = to/a blow, to/a hit, etc. in the metaphorical sense:

"John's death came as a blow." > John's death was a blow > John's death was a great upset.

From this, the meaning "upset" took a further figurative step - "turning something (the current circumstances) over in an unpleasant way." Hence, to/a tip.

References from A Dictionary of the Older Scottish Tongue (up to 1700)

Cowp, Coup, n.1 [e.m.E. coupe, ME. caupe a stroke, blow. Cf. Cowp v.1]

An upset, overturning. — Stewart 4135. Sum gat ane coup gart all hir tymmaris crak;

Lynd. Sat. 2430. I man rin fast, in cace I get ane coup [B. cowp];

*Cowp, Coup, v.1 Also: cowpe. [Cf. ME. cowpe (rare) to strike.]

1. tr. and intr. To turn up; to upset, overset, overturn. Knox II. 15.

Melvil Mem. 404. What soeuer he be that reposes upon his gud seruice, is commonly cowped and wraked;

Adamson Muses Thr. 136. The whirling stream will make our boat to coup;

Which seems to have led to

2. To empty out by overturning.

1653 Sir J. Hope Journal 155. [I began] to inspect the earth about it & I thoght it lay all in little heapes as if it had been new coupped out of hurlebarrowes;