Question: what is the difference between root word and stem word?
Answer: A root is the basic part always present in a lexeme. ... In the form 'untouchables' the stem is 'untouchable', although in the form 'touched' the stem is 'touch'; in the form 'wheelchairs' the stem is 'wheelchair', even though the stem contains two roots. A base is any form to which affixes of any kind can be added.