This is the 8397th most frequent Japanese word.
恐れる
To fear; to be afraid of.
The word '恐れる' is used to express fear or being afraid of something, in this case, failure.
彼は失敗を恐れて挑戦しない。
He is afraid of failure and does not challenge himself.
In this sentence, '恐れる' describes a natural fear or instinct of animals towards predators.
動物たちは捕食者を恐れる。
Animals fear predators.
Here, '恐れる' conveys a personal worry or anxiety about a potential situation, namely falling ill.