A transit hotel is a hotel inside or beside an airport terminal, built for passengers between flights and often selling rooms by the block of hours rather than the night.
Large hub airports usually have at least one, and passengers use the term for several things at once. Strictly, a transit hotel sits airside, beyond passport control, so a passenger can sleep without formally entering the country. Loosely, travellers apply it to any hotel attached to or a short walk from the terminal, and to the day-room rates many airport hotels sell by the hour.
For a booking the distinction is not academic. A room airside of security can only be reached by someone holding a boarding pass, which a visiting therapist does not have. An in-room booking therefore needs a landside room: one reached from the public side of the airport, from the street or the plaza, without crossing a border control. If you are unsure which you have, the hotel's own confirmation usually says whether guests must clear passport control first. Tell the office which it is in your first message; it spares both of you a wasted journey.
Day rooms rented for a block of hours are what turn a long connection into something usable. Match the booking to the block, not the other way round. A six-hour day room taken from 10:00 holds a ninety-minute session comfortably if it starts around 12:00, leaving time beforehand to wash off the flight and time afterwards to rest before checkout. Ask the hotel about checkout flexibility before you write to the office, not after.
A transit or terminal hotel is an airport address, so everything runs by arrangement: a start agreed in writing, and half the ladder price sent electronically after acceptance, before she leaves. Two hours, EUR 360, confirms with EUR 180, and the other EUR 180 is paid in the room. The guide to Schiphol-area hotel types compares the buildings, and layover sets out how to measure the gap.
One hour EUR 180 through to eight hours at EUR 1,250. Forty to sixty minutes anywhere in the centre; the Schiphol airport hotels by arrangement.