absorptivity

The story

1. Latinabsorbeō
2. Old Frenchassorbir
3. Middle Frenchabsorber
4. Englishabsorb
5. Englishabsorptive
6. English todayabsorptivity

From absorptive + -ity.

First known use, by meaning

• First attested in the mid 19ᵗʰ century. The quality of being absorptive; absorptiveness.
• First attested in the mid 19ᵗʰ century. The fraction of radiation absorbed by a surface to the total radiation incident on the surface.