Augment

1. A vowel prefixed, or a lengthening of the initial vowel, to mark past time, as in Greek and Sanskrit verbs.
2. To enlarge or increase in size, amount, or degree; to swell; to make bigger; as, to augment an army by reeforcements; rain augments a stream; impatience augments an evil.
3. To add an augment to.
4. Enlargement by addition; increase.
5. To increase; to grow larger, stronger, or more intense; as, a stream augments by rain.