WordNet
                    terrestrial dynamical time
                    
                        
                
                                                                    n. (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 [syn: terrestrial time, TT, TDT, ephemeris time]
Wikipedia
                    Terrestrial Dynamical Time
                    
                        
                
                                                                    - redirect Terrestrial Time