Joy

joy
noun
\ˈjȯi\

: a feeling of great happiness
: a source or cause of great happiness : something or someone that gives joy to someone
: success in doing, finding, or getting something

Full definition:

1
a :  the emotion evoked by well-being, success, or good fortune or by the prospect of possessing what one desires :  delight
b :  the expression or exhibition of such emotion :  gaiety

2 :  a state of happiness or felicity :  bliss
3 :  a source or cause of delight