Rashi on Exodus 29:20/רש"י על שמות כ״ט:כ׳

1תנוך — This is the inner cartilage which is within the ear, which they call tendrons in old French (cf. Rashi on Leviticus 14:14).

2בהן ידם — i. e. the thumb; and the blood was placed on the middle joint (Chullin 11a).