[stɛməˈtɒlədʒɪ]
Stemmatology is the scientific study involving a text's stemma codicum. It is usually concerned with reconstructing such a stemma, but may also study stemmata in a more abstract sense. The term is usually used synonymously to stemmatics. As with many other fields the endings -ology (from λόγος 'word, meaningful or scientific utterance') and -ic(s) (the adjective forming suffix -ικὴ with an intended feminine τέχνη 'art, field of study') tend to be used for the same purpose, namely to label a 'science of X'.
If a difference between the two terms is perceived, stemmatology is the wider term, whereas stemmatics may be confined to the Lachmannian method.
DE: Stemmatologie
FR: stémmatologie
IT: stemmatologia