absorptiometer

The story

1. Proto-Indo-European*h₂ep
2. Proto-Indo-European*h₂epó
3. Proto-Italic*ap
4. Latinab
5. Latinab-
6. Proto-Indo-European*srebʰ-
7. Proto-Indo-European*srobʰéyeti
8. Proto-Italic*sorβeō
9. Latinsorbeō
10. Latinabsorbeō
11. Latinabsorptiō
12. Englishabsorption
13. Proto-Indo-European*med-
14. Proto-Indo-European*meh₁-
15. Ancient Greekμέτρον (métron)
16. English todayabsorptiometer

From absorption + -ometer (“measure”).

First known use, by meaning

• First attested in the late 19ᵗʰ century. An instrument that computes the absorption rate by measuring the pressure of the gas; a colorimeter for liquids.
• First attested in the mid 20ᵗʰ century. An instrument used to measure the amount of radiation or light absorbed.