Letters that make UT1
t, u, 1 are letters that make 'UT1'
1 possible definitions for 'UT1'
Under this definition, ut1 is a noun and has the following properties:
Greenwich Mean Time, Greenwich Time, GMT, universal time, UT have the same meaning as 'UT1'
'UT1' can be a type of time.
coordinated universal time, UTC are types of 'UT1'.