The phrase "great zest" means having an enthusiastic and energetic attitude towards something or a strong enjoyment and excitement about doing something. Full definition
For example, he continues to criticize with great zest the industry's missed chances to position its authors with effective online marketing techniques. (porteranderson.com)
Horses are very vocal and enjoy speech, whether to a few or to an audience of thousands.They appear to have great zest for life, and have the reputation of being courageous, but inside they are somewhat timid and require a catalyst for any forward motion. (loveawake.com)
livers on its promise of more meaningful desire for your partner, feeling better about yourself, a more resilient relationship, and greater zest for life. (crucible4points.com)