| 1 | Middle English | glade | A gleam of light, bright space, an open space; an... |
| 2 | Old English | glæd | glad |
| 3 | Proto-West Germanic | glad | shining, shiny, radiant; bright, cheery,... |
| 4 | Proto-Germanic | gladaz | shining, shiny, radiant; bright, cheery,... |
| 5 | Proto-Indo-European | gʰladh- | — |
| 6 | Proto-Indo-European | ǵʰel- | to shine, glimmer, glow; to shimmer, gleam;... |