The term 'grunge' as a marketing thing.

All of those bands where on their second, third or fourth album by the time they got big in the early 90s.

That sound just wasn't mainstream, but there was certainly something vibrant happening in indie rock at the time, moving towards a heavier sound but melodic sound. The Smithereens really don't get enough credit in aftersight - I blame their slick big label 80's rock production values.

UltraMegaOK, Bleach, GlueyPorchTreatments, TouchmeI'msick and a bunch of other core 'Grunge' albums where all released by 1988-1989.

It just took a few years for the marketing people to all agree on a name for what was going on with all the independent rock labels that had sprung up all over the country and specifically the seattle/oregon scene.

So yeah maybe the name was a marketing term around for a short time, but by 1994 most of the 'grunge' bands had been around for 6-8 years and back in 1988 where known to people into indie rock and had dedicated regional and small national fanbases before the 1990s. Remember Nirvana was hoping to sell 100,000 records with Nevermind and have a Sonic Youth sized successful career - that takes some pre-existing fan base at least (hence the SubPop Singles Club).

When I saw Nirvana in 89 the club was packed full and we where on the opposite coast. Word of mouth was a thing. To give you an idea of what a different world that concert was the first time teenage me ever saw a girl with a tattoo on the back of her neck - people with piercings and tattoos where still firmly in the camp of being viewed as spooky weirdos and dirtbag hippies. The malls where still selling shit like Milli Vanilli and Motley Crue to teenagers and the entire indie rock scene was still largely a subculture of musicians, music nerds, artists and college radio heads trying their hardest to succeed artistically without being viewed as a 'sell out'.

Source :80's/90's hipster, SubPop Singles Club member, Melvins fan, etc.