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somehow; somewhat; seemingly
彼女は心成しか疲れて見えた。
She seemed somehow tired today.
部屋の空気が心成し冷たく感じた。
The air in the room felt somewhat colder than usual.
事件の後、彼の態度は心成しかよそよそしく感じられた。
After the incident, his attitude seemed somehow distant.