I helped a friend of mine’s mother sort through books the other day.
Her mother is of British decent, and as such typically uses much more eloquence than the average American.
“This book stays, this book goes to Half Price, and this one… is rubbish.”
And that’s my new favourite word.
I hear “rubbish” a lot and have started to use it too.
One word that I think is underused is “reckon”. It’s less vague than “guess” and less precise than “estimate”. In fact, it could replace the non-word “guesstimate” with no loss of fidelity.