noun
- A soft silvery metallic element of the rare earth group; isotope 170 emits X-rays and is used in small portable X-ray machines; it occurs in monazite and apatite and xenotime.
- synonyms: thulium, atomic number 69
WordNet 3.0 © 2006 by Princeton University
| APA | WordNet. (2010). tm. Retrieved September 21, 2026, from http://smartdefine.org/tm/definitions/1316485 |
| Chicago | WordNet. 2010. "tm" http://smartdefine.org/tm/definitions/1316485 (accessed September 21, 2026). |
| Harvard | WordNet 2010, tm, Smart Define, viewed 21 September, 2026, <http://smartdefine.org/tm/definitions/1316485>. |
| MLA | WordNet. "tm" 23 October 2010. Web. 21 September 2026. <http://smartdefine.org/tm/definitions/1316485> |