English Dictionary

In the broadest sense, a process or series of processes by which the living organism as a whole (or its component parts or organs) is maintained in its normal condition of life and growth.
Source : opted (103694)  - auto

In a more limited sense, the process by which the living tissues take up, from the blood, matters necessary either for their repair or for the performance of their healthy functions.
Source : opted (103695)  - auto

That which nourishes; nutriment.
Source : opted (103696)  - auto