Which compound is known as lunar caustic?

Which compound is known as lunar caustic?

کونسا مرکب قمری کاسٹک کے نام سے جانا جاتا ہے؟
Explanation

Silver nitrate (AgNO3) is a strong oxidizing agent and a caustic substance.

It is also known as "lunar caustic" due to its historical use to treat lunar burns (sunburn).