Explanatin for 'pad'

If I insert some lyrics, with melismas and dashes opening Format/Style/Lyrics in the right part of the dialog box I can adjust some features (micro Inspector). Pad as Input devices (Touchpad, joypad or controller)
(But maybe I'm saying some nonsense ...)

Without being a native speaker, the one should be the distance between syllable and dash, the other the distance between melisma and syllable.

I'm a native speaker, Pad is a verb indicating to add space around an item. I would expect the word "Padding" in the phrase 'Lyrics dash padding' indicating this is how much space is put around a dash (same with melisma). If one wanted to use the word Pad to make the phrase shorter, they should say "Pad lyrics dash" or "Pad Melisma" but as a native speaker I understand in improper English and don't really object to it.