1) With respect to function 
• (adv.) In a functional manner; as regards normal or appropriate activity.
Func'tion·al·ly adverb In a functional manner; as regards normal or appropriate activity. « The organ is said to be functionally disordered.» Lawrence. 
[adv] - with respect to function
functionally 1. Capable of operating or functioning. 2. Having or serving a utilitarian purpose. 3. Capable of serving the purpose for which has been designed.
adverb with respect to function; `the two units are functionally interdependent`