Use 'rapturous' to describe a very strong feeling of happiness, more intense than 'happy' or 'glad'. Her rapturous smile was infectious.
Pro Tip 2/3
Excitement Overwhelm
'Rapturous' often implies being so thrilled that one is almost overwhelmed by their emotions. He was rapturous at the sight of the surprise party.
Pro Tip 3/3
Audience's Praise
Use 'rapturous applause' to convey an audience's exceptionally enthusiastic response to a performance. The singer was greeted by rapturous applause after her stunning performance.