Here are some other words related to "silent":
* Безмолвный (bezmolvny) - literally "without a word", meaning very silent, almost completely still
* Немой (nemoy) - mute, unable to speak
* Тишина (tishina) - silence, quietness
The specific word you choose will depend on the context. For example, "тихий" is a good choice for a quiet room, while "безмолвный" might be more appropriate for a completely still forest.