A person who protects, watches over, or is legally responsible for someone or something. Often used in formal, legal, or fantasy contexts.
彼は弟の法的な守護者になった。
He became the legal guardian of his younger brother.
その寺院の守護者は、毎日祈りを捧げている。
The custodian of the temple offers prayers every day.
Compound of 守護 (shugo, 'protection') + 者 (sha, 'person'). The exact historical derivation is uncertain, but the kanji composition directly reflects the meaning.