The New Hacker's Dictionary

tty /T-T-Y/, /tit'ee/ n.

The latter pronunciation was primarily ITS, but some Unix people say it this way as well; this pronunciation is not considered to have sexual undertones.

1. A terminal of the teletype variety, characterized by a noisy mechanical printer, a very limited character set, and poor print quality. Usage: antiquated (like the TTYs themselves). See also bit-paired keyboard.

2. [especially Unix] Any terminal at all; sometimes used to refer to the particular terminal controlling a given job.

3. [Unix] Any serial port, whether or not the device connected to it is a terminal; so called because under Unix such devices have names of the form tty*. Ambiguity between senses 2 and 3 is common but seldom bothersome.

tube //

1. n. A CRT terminal. Never used in the mainstream sense of TV; real hackers don't watch TV, except for Loony Toons, Rocky & Bullwinkle, Trek Classic, the Simpsons, and the occasional cheesy old swashbuckler movie.

2. [IBM] To send a copy of something to someone else's terminal. "Tube me that note?"

tube time // n.

Time spent at a terminal or console. More inclusive than hacking time; commonly used in discussions of what parts of one's environment one uses most heavily. "I find I'm spending too much of my tube time reading mail since I started this revision."

tunafish // n.

In hackish lore, refers to the mutated punchline of an age-old joke to be found at the bottom of the manual pages of tunefs(8) in the original BSD 4.2 distribution. The joke was removed in later releases once commercial sites started using 4.2, but apparently restored on the 4.4BSD tape and in {Net,Free,Open}BSD. Tunefs relates to the 'tuning' of file-system parameters for optimum performance, and at the bottom of a few pages of wizardly inscriptions was a 'BUGS' section consisting of the line "You can tune a file system, but you can't tunafish". Variants of this can be seen in other BSD versions, though it has been excised from some versions by humorless management droids. The [nt]roff source for SunOS 4.1.1 contains a comment apparently designed to prevent this: "Take this out and a Unix Demon will dog your steps from now until the time_t's wrap around."

[It has since been pointed out that indeed you can tunafish. Usually at a canning factory... --ESR]