In his blood
Metaphorically: it characterizes a person's personality; an inseparable part of their nature.
(Modern Hebrew)
Translation
Expression (Hebrew)
טָבוּעַ בְּדָמוֹ
Definition (Hebrew)
בְּהַשְׁאָלָה: מְאַפְיֵין אֶת אִישִׁיּוּתוֹ. חֵלֶק בִּלְתִּי נִפְרָד מִמַּהוּתוֹ.
(הָעִבְרִית הַחֲדָשָׁה)