This is the 506th most frequent Hebrew word.
תקופת
"Period" or "era."
Here, "תקופת" is used to refer to a specific era defined by noticeable changes.
אנו חיים בתקופת השינויים הגדולים.
We are living in the era of significant changes.
In this sentence, "תקופת" denotes a time during a certain season, namely winter.
בתקופת החורף קר מאוד בצפון הארץ.
During the winter season, it is very cold in the north of the country.
Here, "תקופת" refers to a distinct period related to exams and preparation for them.