There is no direct, single-word translation for "silverback gorilla" in Chinese. You will need to use a descriptive phrase. Here are a couple of options:
1. 银背大猩猩 (yín bèi dà xīng xīng)
This literally translates to "silver back big ape," which is a common and accurate way to refer to a silverback gorilla.
2. 背部银色的雄性大猩猩 (bèi bù yín sè de xióng xìng dà xīng xīng)
This is a more detailed description, meaning "male gorilla with silver back."
You could also use a more poetic translation like:
3. 银光闪耀的雄性大猩猩 (yín guāng shǎn yào de xióng xìng dà xīng xīng)
This translates to "male gorilla with shining silver back," which is more evocative.
Ultimately, the best translation will depend on the context and the level of formality you need.