Yes, maximum take-off weight. The maximal authorized/possible weight for an aircraft while taking-off.
It was late yesterday but nevertheless thanks for the correction. I will correct it.
Actually there is no information about the payload given on those tweets and a payload of 1100 kg is obviously impossible for a drone of this size and with its known features.
BTW I found one of those threads that deals with the earlier Saqr series (1 to 4) and in that thread there is plenty of video material of the drone in action.
There are also rumors of it having been used in Yemen.
https://defence.pk/pdf/threads/saud...-showing-indigenous-drone-tests.643940/page-2
For those interested.
The above drone (Saqr 1-B) is a newer model.