In Ger. Mordent means only the lower mordent. Examples are:
In the case of the upper mordent these ‘crushed in’ notes are the main note itself and the note above; if the latter is to be inflected in any way the necessary sign (♯♭♮×♭♭) appears above the mordent sign.
In the case of the lower mordent the ‘crushed in’ notes consist of the note itself and the note below; if this latter is to be inflected in any way the necessary sign appears below the lower mordent sign (the interval is generally that of a semitone).
There is a confusion of terminology. The terms ‘mordent’ and ‘inverted mordent’ are very commonly used for the two forms, but some call the first one shown above the ‘mordent’ and the second one the ‘inverted mordent’, and others reverse these titles. The one way of avoiding all misunderstanding is always to use the words ‘upper’ and ‘lower’. In addition to these 2 forms, others were used by earlier composers but in modern edns. those are set out in full. See also acciaccatura.
mor·dent / ˈmôrdnt/ • n. Mus. an ornament consisting of one rapid alternation of a written note with the note immediately below or above it in the scale (sometimes further distinguished aslower mordent andupper mordent). The terminverted mordent usually refers to theupper mordent.