cổ thụ

Etymology
.

Noun

 * 1)  an old tree; an ancient tree

Usage notes

 * The noun phrase cổ thụ is sometimes used as an example of "redundancy" in Vietnamese (native cây and Sino-Vietnamese  both mean "tree"), and occasionally chalked up to the ignorance of the average Vietnamese speaker about Sinitic morphemes. Notwithstanding the fact that such "redundancy" was common even when Sinology/Chinese philology was still popular in Vietnam, cây here is functionally not a noun, but a classifier modifying the head noun.