O'clock
O'clock was a measurement of time as displayed on a clock. (TOS: "The Return of the Archons") The term could also be used to indicate the relationship between one's present location and that of an incoming enemy combatant or ship, with the former being compared to the center of an analog clock face and the latter to the corresponding position of a number from 1-12 on it. (TOS: "The Galileo Seven"; TNG: "Datalore")
12 hour time notations were divided between __ o'clock in the "morning" and "evening".
Saying that one was expected to arrive at "___ o'clock sharp" indicated a desire for punctuality. (DS9: "The Nagus")
A hat that Katrot bought from a woman on Angel I claimed "It's Romulan ale o'clock somewhere." (i.e. time to drink some of the beverage) (LD: "Empathological Fallacies")