וְשָׁחַ֨ט אֹת֜וֹ עַ֣ל יֶ֧רֶךְ הַמִּזְבֵּ֛חַ צָפֹ֖נָה לִפְנֵ֣י יְהוָ֑ה וְזָרְק֡וּ בְּנֵי֩ אַהֲרֹ֨ן הַכֹּהֲנִ֧ים אֶת־דָּמ֛וֹ עַל־הַמִּזְבֵּ֖חַ סָבִֽיב׃
e o imolará ao lado do altar que dá para o norte, perante o SENHOR; e os filhos de Arão, os sacerdotes, espargirão o sangue em redor sobre o altar.
Rashi on Leviticus
על ירך המזבח means ON THE SIDE OF THE ALTAR (cf. Rashi on Exodus 40:22).
Rabbeinu Bahya
Siftei Chakhamim
On the side. The side is called “thigh” because the thigh is on the side; similarly (Shemos 26:22): “ולירכתי המשכן (For the end of the mishkon),” (Ibid. 27): “לירכתים ימה (of the western [back] wall)” — [means] the side.