A person who dislikes or distrusts humankind. A somewhat formal or literary term; in casual speech, 人間嫌い (にんげんぎらい) is more common.
He is a misanthrope and avoids meeting people.
From 厭 (en, 'dislike') + 人 (jin, 'person') + 者 (sha, 'person'), literally 'person who dislikes people'. The exact historical derivation is uncertain, but it follows a standard Sino-Japanese compound pattern.