Green’s Dictionary of Slang

telephone n.

1. (Can.) a bilingual or multilingual Canadian who moves between the two national groups – Anglophone and Francophone – and is generally despised by both.

[US]Maledicta III:2 182: Telephones. A somewhat obscure reference to those bilingual or multilingual Canadians who act as go-betweens, assisting the French to understand the English, the English the French, and despised by both groups.

2. (US campus) a euph. for toilet, e.g. I have to use the men’s telephone.

[US]Eble Campus Sl. Mar. 6: telephone – toilet: I have to use the men’s telephone. Or, I hear the phone ringing.

3. (Aus. prison) a means of inter-cell communication in prison by tapping on the plumbing pipes.

[Aus]Tupper & Wortley Aus. Prison Sl. Gloss. 🌐 Telephone. A means of communication within prisons whereby the interconnecting plumbing between toilets is cleared of water allowing messages to be passed along prison blocks.
[Aus]B. Matthews Intractable [ebook] I walked over to my toilet and began pushing the water out of the bowl. The ‘Grafton [prison] telephone’ was the precursor to every telecommunication option [...] The downside [...] was that it forced you to breathe the fetid air the whole time you were on the phone.

4. (UK Und.) a scar in the form of a curving line from the corner of the mouth to the earlobe, inflicted on an informer’s face.

[UK]P. Baker Blood Posse 232: I gave him a telephone cut from the tip of his ear to the point of his chin.
[UK]N. ‘Razor’ Smith A Few Kind Words and a Loaded Gun 18: Striping is cutting someone across the face, usually in a curving line that stretches from the corner of the mouth to the earlobe. This kind of scar is also called a ‘telephone’ and indicates that the recipient has been talking to someone who is definitely non grata in criminal circles.

5. (N.Z. prison) a line used to pass contraband from one prisoner to another.

[NZ]D. Looser Boobslang [U. Canterbury D.Phil. thesis] 187/2: telephone n. 1 a line sent from one inmate to another in order to pass illegal contraband; usually made from a surgical glove and a length of (cassette) tape .

In phrases

big white telephone (n.)

the lavatory.

[UK]Guardian 27 Mar. 10/4: Ockers are Bazzer Mckenzie type Aussies — all beer gut, shorts and singlets [...] chundering down the big white telephone.
[Aus]B. Humphries Traveller’s Tool 81: Swallow a crook one and you’ ll spend the next few days on your knees putting a long distance call on the big white telephone.
Stdney Morn. Herald 26 Oct. 9/4: ‘The big white telephone’ in which prisoners empty their toilets and converse through the sewerage.
[Aus]Age (Melbourne) 7 Dec. 130/5: Australia has much of which to be proud [...] drain the dragon, syphon the python, (point percy at the porcelain), having a liquid laugh down the great white telephone.
[US]Eble Sl. and Sociability 72: Big white phone is a metaphor for toilet.
[NZ]McGill Reed Dict. of N.Z. Sl. 129: long-distance call on the big white telephone Vomiting into the toilet bowl. ANZ.
speak into the big white telephone (v.) (also shout down the..., talk to God on the…)

(orig. US) to vomit.

[Aus]C. Bowles G’DAY 5: Even popular Bazzerisms like ‘driving the porcelain bus’, ‘shouting down the great white telephone’, or ‘having a Technicolour yawn’ are rare. Most good Australians just ‘chuck up’, and carry on drinking.
[UK]K. Lette Mad Cows 152: Miming the Princess of Wales talking to God on the big, white telephone.
[UK]Observer (London) Restaurants 17 Jan. 198/1: One [...] of my experiemnts with crustacea will result in the subsequent 24 hours being spent howling miserably at my maker down the big white telephone.
[NZ]McGill Reed Dict. of N.Z. Sl. 196: speaking into the big white telephone Vomiting into the loo.
[UK]N. ‘Razor’ Smith Raiders 36: While the man was talking to God on the big white telephone Wayne was figuring out his strategy.
Twitter 31 Dec. 🌐 I think he was remorseful though as, at the end, he was trying to contact God on the big white telephone in the Bathroom.
talk to Ralph (on the big white telephone) (v.) [ralph v.]

(orig. US campus) to vomit.

[US]Eble Campus Sl. Apr. 4: talk to Ralph on the big white telephone – to vomit.
[US]M. Belmonte Computer Science and Why (1993) 🌐 I was struck with [...] the plethora of words and phrases meaning ‘vomit’ and/or ‘to vomit’ [...] At most American colleges and universities, a weekend cannot pass without seeing multitudes [...] talk to Ralph.
[US]Eble Sl. and Sociability 72: Talk to Ralph on the big white phone is a clever embellishment of ralph, which means ‘to vomit’, and which probably originated as an onomatopoeic approximation.
Berkshire Eagle (Pittsfield, MA) 2 May 19/1: Drinking with kids who will be ‘worshipping the porcelain god’ or ‘talking to Ralph on the big white telephone’.
talk to the (big) white telephone (v.)

(orig. US campus) to vomit.

[US]M. Belmonte Computer Science and Why (1993) 🌐 I was struck with [...] the plethora of words and phrases meaning ‘vomit’ and/or ‘to vomit’ [...] At most American colleges and universities, a weekend cannot pass without seeing multitudes [...] talk to the big white telephone.
[Aus]G. Seal Lingo 135: As over-indulgence in alcoholic beverages may induce vomiting, the Lingo is well stocked with terms for this, including [...] talk to the white telephone.