| English noun: Tm | |||
| 1. | Tm (substance) 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 | atomic number 69, thulium | ||
| Broader (hypernym) | metal, metallic element | ||
| Substance meronym | apatite, monazite, xenotime | ||