TWEAK
pinch, tweak
(noun) a squeeze with the fingers
tweak, fine-tune
(verb) adjust finely; “fine-tune the engine”
pluck, tweak, pull off, pick off
(verb) pull or pull out sharply; “pluck the flowers off the bush”
tweak
(verb) pinch or squeeze sharply
Source: WordNet® 3.1
Etymology
Verb
tweak (third-person singular simple present tweaks, present participle tweaking, simple past and past participle tweaked)
(transitive) To pinch and pull with a sudden jerk and twist; to twitch.
(transitive, informal) To adjust slightly; to fine-tune.
(transitive) To twit or tease.
(intransitive, US, slang) To abuse methamphetamines, especially crystal meth.
(intransitive, US, slang) To exhibit symptoms of methamphetamine abuse, such as extreme nervousness, compulsiveness, erratic motion, excitability; possibly a blend of twitch and freak.
(intransitive, US, slang) To exhibit extreme nervousness, evasiveness when confronted by law enforcement or other authority (e.g, customs agents, border patrol, teacher, etc.), mimicking methamphetamine abuse symptoms.
Noun
tweak (plural tweaks)
A sharp pinch or jerk; a twist or twitch.
A slight adjustment or modification.
Trouble; distress; tweag.
(obsolete, slang) A prostitute.
(cryptography) An additional input to a block cipher, used in conjunction with the key to select the permutation computed by the cipher.
Source: Wiktionary
Tweak, v. t. Etym: [OE. twikken, originally the same word as
twicchen; cf. LG. twikken. See Twitch.]
Definition: To pinch and pull with a sudden jerk and twist; to twitch; as,
to tweak the nose. Shak.
Tweak, n.
1. A sharp pinch or jerk; a twist or twitch; as, a tweak of the nose.
Swift.
2. Trouble; distress; tweag. [Obs.]
3. A prostitute. [Obs.] Brathwait.
Source: Webster’s Unabridged Dictionary 1913 Edition