Week
A week was small number days grouped together as part of a calendar system. On Earth, a week was seven days.

The colony ship  transmitted weekly status reports during the Terra Nova Expedition. These reports were reviewed by Ensign Travis Mayweather in 2151. ()

On June  2151, Sub-commander T'Pol was aboard  for nine weeks and four days. ()

In August of 2151, Enterprise was sent to assist the Earth Cargo Service freighter  as the nearest Starfleet vessel would need three weeks to arrive but Enterprise would only need one day and a half at maximum warp. ()

Takret only needed to sleep once a week. ()

Travis Mayweather and his father once took shelter in the ship's core to protect against a class 3 neutronic storm. They were there for six weeks. ()

Romulans also grouped their days into weeks.  On the third day of the Romulan week the Romulan Senate was not in session. () 

In 2380, only one week after buffer time was eliminated on the USS Cerritos, the entire ship's entire crew began performing terribly, and this caused chaos to erupt all over the ship. ()

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Time measurements