Gt.Gt. (also Gt British English) adjective [only before noun] the written abbreviation of Great, used in names: 
Gt Britain
Gt Britain- unprecedentedly
- unpredictability
- unpredictable
- unpredictably
- unprepared
- unprepossessing
- unpretentious
- unprincipled
- unprintable
- unproductive
- unprofessional
- unprofessionally
- unprofitable
- unpromising
- unprompted
- unpronounceable
- unprotected
- unproven
- unprovoked
- unpublished
- unpunished
- unputdownable
- unqualified
- unquenchable
- unquestionable