subject of examination; test subject
Technical term used in medical, scientific, or testing contexts for the person, animal, or sample being examined or tested.
In clinical trials, the health status of the test subjects is checked regularly.
This inspection device visualizes the internal structure by irradiating the subject with X-rays.
Compound of 被 (hi, 'receiving') + 検 (ken, 'examination') + 体 (tai, 'body'). The exact historical derivation is uncertain, but the word follows a common Sino-Japanese pattern for technical terms.