These are
Geological periods
and the answers are:
1. Ordovician, NO(COVIDI*COVID* + I)RA*
2. Triassic, RACIS(IS<)T*
3. Devonian, DE(VON + I)AN
4. Jurassic, JURA + 'S + ..S ..I ..C
5. Siderian, SI(AIRED*)N
6. Cretaceous, C(CREATE*)O + US
7. Ediacaran, CANADIANRYE* - NY
8. Ectasian, ...ECT AS I AN...
9. Statherian, ..STAT.. + HERNIA*
10. Carboniferous, CARBON + IF + ..ER + O.. + U'S (universities)