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to freeze; to congeal
to concentrate one's attention on; to devote oneself to something; to ponder; to meditate
「凝らす」 has another reading with different meanings.
料理人は盛り付けに工夫を凝らして客を喜ばせた。
The chef pleased guests by elaborating on the presentation.
寒さで手を凝らしてしまいました。
My hands got numb from the cold.
彼女は衣装に趣向を凝らしてパーティーに出席した。
She attended the party with an elaborately designed costume.