What does inert mean?
You are correct!
From our dictionary:in•ert
Pronunciation: (in-ûrt', i-nûrt'), [key]
—adj.
1. having no inherent power of action, motion, or resistance (opposed to active): inert matter.
2. Chem.having little or no ability to react, as nitrogen that occurs uncombined in the atmosphere.
3. Pharm.having no pharmacological action, as the excipient of a pill.
4. inactive or sluggish by habit or nature.