Green’s Dictionary of Slang

noodle n.1

[ety. unknown; ? SE nod or SE noodle, a fool or var. of noddle n.]

1. [19C+] the human head.

2. [20C+] used fig. to denote intelligence, the mind [fig. use of sense 1].

In derivatives

noodly (adj.)

[1900s] (US) crazy.

In compounds

noodle bowl (n.)

[2000s] the brain.

noodlehead (n.) (also noodle, noodlebrain) [-head sfx (1)]

[late 19C+] (US) a dull, stupid person; thus adj. noodleheaded, stupid.

noodle juice (n.)

[1920s] (US) tea.

In phrases

house of noodles (n.)

[mid-19C] the House of Lords.

off one’s noodle (adj.)

(US) eccentric.

out of one’s noodle (adj.)

[1940s+] (orig. US) experiencing the effects of a drug.