quill·wort 
(kwĭlwûrt′, -wôrt′)
(kwĭlwûrt′, -wôrt′)n.
Any of several vascular, spore-bearing, aquatic or marsh plants of the genus Isoetes, having quill-like leaves.
- radiolucency
- radiolucent
- radiolysis
- radiolytic
- radioman
- radiometer
- radiometric
- radiometric dating
- radiometry
- radiomimetic
- radionuclide
- radiopacity
- radiopaque
- radiopharmaceutical
- radiophone
- radiophonic
- radiophoto
- radiophotograph
- radiophotography
- radioscopic
- radioscopical
- radioscopy
- radiosensitive
- radiosensitivity
- radiosonde