Week
From Tardis Wiki, the free Doctor Who reference
A week was a period of time equal to seven days.
The young Jeanne-Antoinette Poisson remarked she had not seen the Tenth Doctor in weeks when he visited her in 18th century France. (TV The Girl in the Fireplace)
The Human-Hath War on Messaline lasted seven days, or "just a week" as Donna Noble put it. (TV: The Doctor's Daughter)
