noddle

The head; the part of the body of an animal or human which contains the brain, mouth and main sense organs.

The head as the seat of mental capacity or intellect.

The back of the head; nape.

To nod repeatedly.

To think or ponder.

“"Noodle that thought around for a while" said Dr. Johnson to his Biblical Interpretations class.”

To fiddle, play with, or mess around.

“If the machine is really broken, noodling with the knobs is not going to fix it.”

To improvise music.

“He has been noodling with that trumpet all afternoon, and every bit of it sounds awful.”

To fish (usually for very large catfish) without any equipment other than the fisherman's own body

“Fred had several lacerations on his hands from noodling for flathead in the river.”

To fossick, especially for opals.