heyday
noun
[ ˈheɪdeɪ ]
• the period of a person's or thing's greatest success, popularity, activity, or vigour.
• "the paper has lost millions of readers since its heyday in 1964"
Similar:
prime,
peak,
height,
high point,
high spot,
peak of perfection,
pinnacle,
acme,
zenith,
day,
time,
bloom,
flowering,
culmination,
crowning point,
prime of life,
best days,
best years,
salad days,
Opposite:
low point,
Origin:
late 16th century (denoting good spirits or passion): from archaic heyday!, an exclamation of joy, surprise, etc.