This is the 519th most frequent Hebrew word.
כשהוא
"When he" or "when it."
Here, כשהוא is used as a conjunction meaning 'when he' to indicate an event happening in the past.
כשהוא הלך הביתה, ירד גשם.
When he went home, it was raining.
In this sentence, כשהוא is used to show a simultaneous condition where one action happens during another.
הוא אוהב לשמוע מוזיקה כשהוא מבשל.
He likes listening to music when he cooks.
Here, כשהוא indicates a condition or state, translating as 'when he is' and describing a temporal or situational context.