Definition:

: marked by or suggestive of high spirits and lively mirthfulness.

Examples: 

Clayton gave a jocund shout when he entered the room and saw the many friends who had come for his surprise 50th birthday celebration.

“The jocund nature of Beethoven’s Second Symphony is in utter contradiction with Beethoven’s pathetic letter expressing the despair of inevitable deafness, both written at approximately the same time.” — D. S. Crafts, The Albuquerque (New Mexico) Journal, 13 Jan. 2012

by MERRIAM-WEBSTER DICTIONARIES.