תחמס Tachmas
Every verse in which this word stands — 2 places, in canonical order, first appearance to last. These are the places the lexicon carries under this word's own entry, counting every form the text writes it in, which is the number on the list.
Named in both kosher lists among the forbidden birds. The renderings run from owl to falcon to nighthawk; the identification is discussed.
וְאֵת בַּת הַֽיַּעֲנָה וְאֶת־הַתַּחְמָס וְאֶת־הַשָּׁחַף וְאֶת־הַנֵּץ לְמִינֵֽהוּ
and the ostrich, and the night-hawk, and the sea-mew, and the hawk after its kinds;
וְאֵת בַּת הַֽיַּעֲנָה וְאֶת־הַתַּחְמָס וְאֶת־הַשָּׁחַף וְאֶת־הַנֵּץ לְמִינֵֽהוּ
and the ostrich, and the night-hawk, and the sea-mew, and the hawk after its kinds;
Quick answers
What is the Hebrew word for tachmas?
Tachmas in Hebrew is תחמס, with a gematria of 508 in the standard method.
How many times is the tachmas mentioned in the Tanakh?
The word stands 2 times in the Tanakh, first at Leviticus 11:16.
A spelling is not a word. The corpus never writes תחמס bare — every one of its places carries a particle or a suffix on the front or the back — so the spelling above is the word's own headword, and the verses listed here are the only door to it.