lignum vitae
noun
lig·num vi·tae ˌlig-nəm-ˈvī-tē 
plural lignum vitaes
1
: the very hard heavy wood of any of several tropical American guaiacums
2
: a tree yielding lignum vitae
Example Sentences
Recent Examples on the Web The scents are created using native flowers — such as hibiscus, lignum vitae, elderflower — from St. Martin, Aruba, St. Thomas and other islands. 
Kavita Daswani, latimes.com, 3 Nov. 2017
Kavita Daswani, latimes.com, 3 Nov. 2017 Word History
Etymology
New Latin, literally, wood of life
First Known Use
1594, in the meaning defined at sense 1
Medical Definition
lignum vitae
noun
lig·num vi·tae ˌlig-nəm-ˈvīt-ē
plural lignum vitaes
1
: any of several tropical American trees of the genus Guaiacum with very hard heavy wood
especially : either of two (G. officinale or G. sanctum) that are sources of guaiacum resin
2
: the wood of a lignum vitae