This modifier is usually applied to Cop or similar investigative roles that receive a result, but can be used on other roles to delay the action itself instead of just the result, such as a Delayed Doctor submitting a target the first Night but only being able to save them the next Night.
For example, for the most common variant of a Delayed Cop, submitting an investigation on Night 1 would return a result on Night 2. Trackers, Watchers, and similar roles would see the action having been performed on Night 1 should they choose a relevant target. Whether a Delayed role can submit an action on the Night a prior action is scheduled to resolve is usually up to the moderator.
This modifier is considered explicitly Non-Normal on mafiascum.net.