The spelling of the word "cardus" can be confusing due to the silent "s" at the end. In IPA phonetic transcription, it is written as /'kɑːdəs/, with a long "a" sound in the first syllable and a schwa sound in the second syllable. The "d" sound is represented by the IPA symbol /d/, followed by the silent "s" at the end. Cardus is a genus of thistle plants with spiny leaves and purple flowers, commonly known as plumeless thistles.
Carduus.
A practical medical dictionary. By Stedman, Thomas Lathrop. Published 1920.
The word "cardus" has its origins in Latin. It comes from the Latin word "carduus", which means "thistle" or "thorny plant". The Latin word "carduus" can be traced back to the ancient Greek word "kardos" with the same meaning.