IPA: /ʌnˈtɔrn/
KK: /ʌnˈtɔrn/
Not damaged or ripped; in perfect condition.
The letter was still untorn, showing it had never been opened.
Untorn → It is formed from "un-" (meaning not) and "torn" (from Old English "teran", meaning to tear). The word "untorn" means not torn or intact.
Think of 'not' ('un-') being added to 'torn' to remember that 'untorn' means something that is not damaged or remains whole.