Linguistics
English 'gl-' words for light aren't a coincidence - the sound cluster carries meaning
Glow, glitter, gleam, glisten, glint, glare: dozens of English words about light or shine start with 'gl-', far more than chance would predict. Linguist J.R. Firth coined the term 'phonestheme' in 1930 for sound clusters like this that carry a recognisable meaning without being a full morpheme - smaller than a word, but not meaningless the way an ordinary phoneme is. English has similar clusters for other senses, like 'sl-' for slippery motion in slide, slick and slither.