Answer:
Quicklime.
Explanation:
Calcium oxide ([tex]CaO[/tex]) derives from calcium carbonate ([tex]CaCO_{3}[/tex], basically calcite) after being calcinated (having [tex]CO_{2}[/tex] removed) and therefore leaving us with 1 Calcium and 1 oxygen atom.
We use the term "lime" to refer to any calcium-based mineral, whereas the term "quicklime" is used to refer specifically to [tex]CaO[/tex].
Hope it helped,
BiologiaMagister