1 about, approximately, nearly, almost, roughly; circa:
There were around a dozen of us in the place.
2 about, everywhere, in every direction, on all sides, all over, throughout:
By this time the savages were all around and we couldn't move.
3 round, about, for everyone or all, US also 'round:
I don't think we have enough food to go around.
4 round, about, all about, everywhere, here and there, hither and thither, hither and yon, far and wide:
The tinker travelled around selling his wares and repairing pots.
5 round, about, surrounding, encompassing, enveloping, encircling, on all sides of, in all directions from, enclosing:
The fields around the castle were cultivated by tenant farmers.
6 about, approximately, roughly; circa:
He was born around the turn of the century.