In the phrases “lyric tenor” or “lyric baritone” what does the word “lyric” signify?

In the phrases “lyric tenor” or “lyric baritone” what does the word “lyric” signify?

In the phrases “lyric tenor” or “lyric baritone” what does the word “lyric” signify?

In the phrases “lyric tenor” or “lyric baritone” what does the word “lyric” signify?