Noun
decimal time (uncountable)
A system of timekeeping in which time is decimalized. For example, a day is divided into 10 decimal hours, each decimal hour into 100 decimal minutes, and each decimal minute into 100 decimal seconds.
Decimal time of day had been introduced in France two years earlier, but was set aside at the same time the metric system was inaugurated, and did not follow the metric pattern of a base unit and prefixed units. Source: Internet