• (n.) A name given to the `big trees` (Sequoia gigantea) of California, and still used in England. See Sequoia.
Wel`ling·to'ni·a noun [ New Latin So named after the Duke of Wellington .] (Botany) A name given to the 'big trees' ( Sequoia gigantea ) of California, and still used in England. See Sequoia . 
Wellingtonia was a former name for the giant trees of California. It was superseded in the late 19th century by the term Sequoia.