The term 'enthusiastic enjoyment' can be summarized by two crossword solutions: 'GUSTO' (5 letters) and 'ZEST' (4 letters). GUSTO is a noun that means great enthusiasm and vigor in the pursuit of something. It is derived from the Latin word 'gustus, ' which means taste. ZEST is also a noun that refers to an eagerness or enthusiasm for something. It is derived from the Middle English word 'zesten, ' which means to sharpen. Both words are often used to describe someone's enthusiasm for an activity or task.