IPA: /ˈheɪdeɪ/
KK: /ˈheɪˌdeɪ/
The time when someone or something is at its most successful or popular.
The band was at its heyday in the 1990s, with hit songs topping the charts.
Heyday originates from the Middle English phrase 'hayday' (meaning 'a time of great success or popularity'). The term is believed to be a combination of 'hay' (referring to the harvest season) and 'day' (meaning a period of time). It signifies a time when things are flourishing or at their peak.
Imagine a time when the 'harvest' ('hay') is at its best, marking a 'day' of great success — that's what heyday means.