UNSCREW
unscrew
(verb) loosen something by unscrewing it; “unscrew the outlet plate”
unscrew
(verb) loosen by turning; “unscrew the bottle cap”
Source: WordNet® 3.1
Etymology
Verb
unscrew (third-person singular simple present unscrews, present participle unscrewing, simple past and past participle unscrewed)
(transitive) To loosen a screw or thing by turning it.
Antonyms
• screw
Source: Wiktionary
Un*screw", v. t. Etym: [1st pref. un- + screw.]
Definition: To draw the screws from; to loose from screws; to loosen or
withdraw (anything, as a screw) by turning it.
Source: Webster’s Unabridged Dictionary 1913 Edition