responsiveness

[ri-spon-siv-nis]

noun

the quality or state of being responsive.
Machinery. the ability of a machine or system to adjust quickly to suddenly altered external conditions, as of speed, load, or temperature, and to resume stable operation without undue delay.

Also re·spon·siv·i·ty

[ri-spon-siv-i-tee, ree-spon-] /rɪ spɒnˈsɪv ɪ ti, ˌri spɒn-/.

Origin of responsiveness

First recorded in 1840–50; responsive + -ness