Best definition
(1) In East London slang, a term of endearment used to describe a grumpy, bitter and twisted old man.

A working sailing boat (“Lune Whammel”) originally designed in the early 1900s and most commonly found in the Lune Estuary / Morecambe Bay, Lancashire, England.
(3) Transitive verb meaning to turn over.

There’s a whammel sailing that Whammel but he’s not going to whammel for us.
whammel: define #2
English Black Country word for dog.
I’m taking the whammel up the cut. Means I’m taking the dog for a walk along the nearby navigational waterway.