/trü-ha-kər/
[analogy with 'trufan' from SF fandom]
n. One who exemplifies the primary values of hacker culture, esp. competence and helpfulness to other hackers. A high compliment.
"He spent 6 hours helping me bring up UUCP and netnews on my FOOBAR 4000 last week -- manifestly the act of a true-hacker."