Full of joy.
From Latin lætabund-us, from lætari 'to be joyful'
Real world usage
1535 Stewart Cron. Scot. II. 505 Of quhois come this nobill king Edmound, As bird on breir wes blyth and letabund.
It seems incongruous to me in a word ending in -bund should have such a pleasant meaning. When I think of -bund words, I think that was such as moribund (at the end of life), cummerbund (at the end of fashion), and Balkansprachbund (a grouping of linguistics similarities among the Balkan languages). It's nice to see that letabund escaped it's unfortunate childhood and grew up to be a happy and well adjusted word.