| a calculus or concretion found in the stomach or intestines of certain animals, esp. ruminants, formerly reputed to be an effective remedy for poison. |
| a chattering or flighty, light-headed person. |
| marsh gas | |
| —n | |
| a hydrocarbon gas largely composed of methane formed when organic material decays in the absence of air | |
marsh gas n.
See methane.