This is the 4713th most frequent Japanese word.
暇
Free time; leisure.
The word '暇' is used here as a noun indicating 'free time' or 'leisure', describing the speaker's availability today.
今日は暇ですから映画を観ます。
Since I have free time today, I'll watch a movie.
In this sentence, '暇な' serves as an adjective modifying '時' (time), suggesting times when the speaker is free or not busy.
暇な時は読書を楽しみます。
During my free time, I enjoy reading.
Here, '暇さえ' is used to emphasize the scarcity or condition of having 'free time' as a prerequisite for traveling.