(Christianity) The week in which the Rogation Days occur.

(chiefly US, idiomatic) The week during which new members are required to undergo undignified rites of initiation or gruelling discipline in order to be accepted into a fraternity, sorority, secret society, military group, etc.

Alternative form of hell week

(Australia) A festival during which finishing high school students celebrate the end of their studies, and associated freedom.

(US) The week leading up to homecoming, during which school students dress up in unusual themed clothing.

Synonym of technical week

The week prior to the opening night of a play, musical, etc., during which technical elements such as costumes, lights, sound, set and makeup are tested during rehearsal.

(astronomy, physics) A unit of length equal to the distance light travels in one week.

(university slang, Canada) A week of activities dedicated to new students at a college or university, held to prepare them for their first academic year.

(Oxford University) The week before the first week of an academic term, when many undergraduates arrive from home.