the week in question; that week
Refers to a specific week previously mentioned or understood from context, often used in scheduling, publications, or formal announcements.
The schedule for that week may be subject to change.
His interview appeared in the magazine published that week.
Compound of 当 (とう, 'this' or 'the relevant') and 週 (しゅう, 'week'). The prefix 当- is commonly used in formal contexts to refer to the matter at hand, as in 当日 (とうじつ, 'the day in question').