adv. On this; hereon. [ 1913 Webster ]
adv.
[ He ] hopes to find you forward, . . .
And thereupon he sends you this good news. Shak. [ 1913 Webster ]
adv. Upon which; in consequence of which; after which. [ 1913 Webster ]
The townsmen mutinied and sent to Essex; whereupon he came thither. Clarendon. [ 1913 Webster ]