1. a stone or similar object formerly believed to be found in the head of a toad and thought to have magical or medicinal properties
Usage: historical
2. a type of volcanic rock, typically dark-colored basaltic rock
Usage: geology

Examples

• Medieval physicians believed that a toadstone could neutralize poison.
• The merchant claimed his toadstone ring would protect against evil.
• Superstitious people once paid high prices for genuine toadstones.
• The geologist identified the dark layer as toadstone from an ancient eruption.
• Toadstone formations are common in certain volcanic regions.
• The old castle was built using local toadstone quarried from nearby cliffs.