aug ‧ ment /ɔːɡˈment $ ɒːɡ-/ BrE AmE verb [transitive]
[ Date: 1300-1400 ; Language: French ; Origin: augmenter , from Late Latin augmentare , from Latin augere 'to increase' ]
formal to increase the value, amount, effectiveness etc of something:
Any surplus was sold to augment their income.
—augmentation /ˌɔːɡmenˈteɪʃ ə n, -mən- $ ˌɒːɡ-/ noun [uncountable and countable]