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to warm oneself; to sun oneself; to warm up; to get warm
お風呂に入って体が温まった。
I warmed up after taking a bath.
午後の日光で部屋が自然に温まってきた。
The room naturally warmed up in the afternoon sunlight.
昨日ボランティアで心が温まる話を聞いた。
I heard a heartwarming story during volunteer work yesterday.