(adv.) At which; upon which; whereupon; -- used relatively.
(adv.) At what; -- used interrogatively; as, whereat are you offended?
Example Sentences:
(1) ), whereat measurements can be taken either using cylindrical graphitic walls or "no walls".
Whereon
Definition:
(adv.) On which; -- used relatively; as, the earth whereon we live.
(adv.) On what; -- used interrogatively; as, whereon do we stand?
Example Sentences:
(1) With the patient in a supine position, the droplets could be positioned over the macula in the preretinal vitreous space, whereon the FTBA PO2 could be influenced by the preretinal oxygen concentration.
(2) The heart was the only one of all the internal organs whereon significant pathologic changes were observed during autopsy.