Of the ubiquity of markup objects

Text objects are entered either as simple strings between double quotes or as \markup blocks that can accept a variety of advanced text formatting and graphical enhancements.

As such, markup blocks may be used:

\markup may additionally be used for lyrics, in chord names, and as dynamics. In fact, it is possible to use \markup to customize the appearance of virtually any object, as demonstrated in this example using various methods.

%% Thanks to Aaron Hill https://lists.gnu.org/archive/html/lilypond-user/2019-01/msg00437.html

\paper {
  paper-width = 8\cm paper-height = 8\cm

\header {
  title = \markup "Header"
  tagline = \markup "(tagline)"

\markup "Top-level markup"

dyn = #(make-dynamic-script #{ \markup \serif "DynamicText" #})

\score {
    \new ChordNames
    \with { majorSevenSymbol = \markup "majorSevenSymbol" }
    \chordmode { c1:maj7 }
    \new Staff {
      \tempo \markup "MetronomeMark"
      \textMark "TextMark"
      \once \override TupletNumber.text = \markup "TupletNumber"
      \tuplet 3/2 {
        \once \override NoteHead.stencil = #ly:text-interface::print
        \once \override NoteHead.text = \markup \lower #0.5 "NoteHead"
        c''8^\markup "TextScript"
        \once \override Rest.stencil = #(lambda (grob)
          (grob-interpret-markup grob #{
            \markup  "Rest"
    \new Lyrics \lyricmode { \markup "LyricText" 1 }
    \new Dynamics { s1\dyn }

[image of music]

LilyPond snippets v2.25.18 (development-branch).