Rashi on Leviticus 14:14/רש"י על ויקרא י״ד:י״ד

1תנוך is the inner wall of the ear. The etymology of the word תנוך is unknown to me, and the compilers of glossaries call it (translate it by) tendron (cf. Rashi on Exodus 29:22).

2בהן means THUMB.