What is the meaning of Cockle?

Any of various edible European bivalve mollusks, of the family Cardiidae, having heart-shaped shells.

The shell of such a mollusk.

One’s innermost feelings (only in the expression “the cockles of one’s heart”).

A wrinkle, pucker

A defect in sheepskin; firm dark nodules caused by the bites of keds on live sheep

The mineral black tourmaline or schorl.

The fire chamber of a furnace.

A kiln for drying hops; an oast.

The dome of a heating furnace.

To cause to contract into wrinkles or ridges, as some kinds of cloth after a wetting; to pucker.

Any of several field weeds, such as the common corncockle (Agrostemma githago) and darnel ryegrass (Lolium temulentum).

To wobble, shake; to be unsteady.

A £10 note; a tenner.

Source: wiktionary.org