Considering (whatever is stated after "that"). Seeing that it's pouring rain and all, how about we reschedule the picnic, huh?
considering...; since... Seeing that she has no money, Sally won't be going shopping. Seeing that it's raining, we won't go to the beach.
Also, seeing as or seeing as how. In view of, inasmuch as. For example, Seeing that you're coming anyhow, I decided not to take notes for you, or Seeing as they liked her first book, they were sure to make a good offer for the second one . The first expression was used by Shakespeare in Julius Caesar (2:2): "Seeing that death, a necessary end, will come when it will come." The variants are colloquialisms and are recorded from the second half of the 1900s, although they probably have been in much longer use orally.
seeing as/that...because; considering that; since: Seeing as we’re both going the same way, can I give you a lift?
See also: seeing