Related Clues:
- What red indicates in litmus tests
- It's been taken for many trips
- Low-pH stuff
- Erstwhile VHS rival
- Alkali balancer
- Lemon juice, e.g.
- __ carotene
- The second Greek letter
- It is neutralized by alkali
- Second letter of the Greek alphabet
- __ rock
- It turns litmus red
- Caustic and biting
- Substance which turns litmus red
- 2nd letter of Greek alphabet