An Etymological Dictionary of Astronomy and Astrophysics

The ratio of energy absorbed by a body to energy incident upon the same body.

Etymology (EN): Absorptivity, from absorptive adj. from → absorb + → -ity, suffix expressing state or condition.

Etymology (PE): Daršamâyi, from daršamâ quality adj. from daršam, present stem of daršamidan + -yi noun suffix.