This is the 613th most frequent Slovak word.
uplynulých
"Uplynulých" means "past" or "elapsed" in English.
Here 'uplynulých' means 'past' and is used as an adjective to describe 'rokoch' (years) in the genitive plural form.
V uplynulých rokoch sme zažili veľa zmien.
In the past years, we have experienced a lot of changes.
In this sentence, 'uplynulých' again means 'past' and modifies 'dní' (days) in the genitive plural, indicating a specific preceding period.
Udalosti uplynulých dní nás hlboko zasiahli.
The events of the past days have deeply affected us.
Similarly, 'uplynulých' functions as an attributive adjective describing 'mesiacov' (months) in the genitive plural, referring to the time just before the present.