1.
ransom
Money demanded or paid for the release of a captive. Used in both literal kidnapping contexts and metaphorically in computing (ransomware).
Literally "money in place of one's body." The word breaks down as 身代 (substitute for a person) + 金 (money).
Common collocations
In modern usage, also appears in computing contexts: 身代金要求型ウイルス or ランサムウェア refers to ransomware that encrypts files and demands payment.