The Collaborative International Dictionary of English v.0.48:
Bon vivant \Bon` vi`vant"\ (b[^o]N` v[-e]`v[aum]N"); pl. Bons vivants (-v[aum]N"z). [F. bon good + vivant, p. pr. of vivre to live.] A good fellow; a jovial companion; a free liver. [1913 Webster]