"T"^^ . "second.n" . . "second.n"^^ . . "fn15schema: (of a state-of-affairs) lasting a sixtieth of a minute; SI time-length unit defined as the duration of 9,192,631,770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the cesium 133 atom."^^ . "n" . "second" . . . "COD: a sixtieth of a minute of time, which as the SI unit of time is defined in terms of the natural periodicity of the radiation of a caesium-133 atom"^^ . . .