amplify

verb4

1. •
   To render larger, more extended, or more intense.

   • [T]he fauour of Princes and Magistrates norysheth, augmenteth, and amplyfyeth all artes and sciences by liberalitie, and extynguysheth the same by miserable couetousnes and parcimonie. — 1561
2. •
   To increase the amplitude of something, especially of an electric current.

   • amplify a signal. It's amplified so you can hear the audio.
3. •
   To enlarge by addition or commenting; to treat copiously by adding particulars, illustrations, etc.; to expand.

   • Troilus and Cressida was written by a Lombard author, but much amplified by our English translator. — 1700
4. •
   To add content that is not present in the source text to the target text, usually to improve the fluency of the translation.