1.  tt(n = noun.time) ephemeris time, tdt, terrestrial dynamical time, terrestrial time - (astronomy) a measure of time defined by Earth's orbital motion; terrestrial time is mean solar time corrected for the irregularities of the Earth's motions;
is a kind of time unit, unit of time

2.  tt(n = noun.location) palau, republic of palau - a republic in the western central Pacific Ocean in association with the United States;
is a kind of country, land, state
is a part of belau, palau, palau islands, pelew

3.  tt(n = noun.location) federated states of micronesia, micronesia - a country scattered over Micronesia with a constitutional government in free association with the United States; achieved independence in 1986;
is a kind of country, land, state
is a part of micronesia
has parts: kolonia, ladrone islands, mariana islands, marianas, caroline islands, marshall islands, ellice islands, tuvalu, kiribati, republic of kiribati, gilbert and ellice islands, nauru, nauru island, pleasant island

tt, abbr.
1 Tourist Trophy.
2 tuberculin-tested.
3 a teetotal. b teetotaller.