noun
Refers to familial lineage or ancestry, often emphasizing inherited traits or status through blood relations.
彼は武士の血筋を引いている。
He is descended from a samurai lineage.
血筋は争えないものだ。
Blood will tell.
家系 is a more formal term for family lineage or genealogy, often used in historical or academic contexts, while 血筋 carries a stronger nuance of inherited blood traits.
血統 is similar but often used for animals (pedigree) or in a more biological sense, whereas 血筋 is more commonly used for human family lines and social status.
Compound of 血 (chi, 'blood') and 筋 (suji, 'line, muscle, thread'), literally 'blood line'. The reading ちすじ is a straightforward combination of the kun'yomi readings of the two kanji.