n.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
同义词:thuliumatomic number 69
英汉双解大词典
TM/ˌtiːˈɛm/
1.
() TM is a written abbreviation for . trademark的缩写