noun
seal of approval; authorization; thumbs up
Figurative use: an authoritative endorsement or official approval, often from a respected person or institution. Sense 2 (thumbs up) is a natural extension of the certification meaning.
See also: 墨付き
先生からお墨付きをもらったので、この方法で進めます。
Since we got the seal of approval from the teacher, we'll proceed with this method.
彼の料理は、有名シェフのお墨付きだ。
His cooking has the thumbs up from a famous chef.
noun
document bearing the shogun's or lord's signature
Historical original meaning: a paper authenticated with the black-ink signature or seal of a shogun or feudal lord.
See also: 墨付き
江戸時代、お墨付きは将軍の権威を示す重要な文書だった。
In the Edo period, an osumitsuki was an important document showing the shogun's authority.