From the pictures I've seen they both seem to be extremely similar indeed. Do you know who invented the word dulcimore, and who invented the word dulcimer?
The Latin root 'dulci' means sweet. Nobody knows who exactly invented the words dulcimer or dulcimore. It goes far back in time, to medieval references to hammered dulcimers. 'Dulcimore' is simply one of various old fashioned variations of names for the same or similar instruments.
Dan:Don't know there is any thing exact in the tradition. Some (I included) use the term Dulcimore to differentiate the traditional pieces from the contemporary pieces. "Dulcimore" was just one of several regional names assigned to an Appalachian folk instrument some 150 year ago? Hog fiddle, scantlin', music box, harmonium to name a few, and those had varying regional mountain pronunciations too!
Right, Dan! So many quaint old names for mountain dulcimers were in use years ago in the US. Indian walking stick, dulcerine, duck slammer, even sometimes just called a Music Box.
I first noticed the particular name 'dulcimore' being used much more frequently by Dan Cox just a few years ago. Before that (for the 30 years i have studied and discussed dulcimers), we all simply talked about 'traditional mountain dulcimers' and 'modern dulcimers'. 'Dulcimore' rarely came up except in online conversations where we were listing quaint old fashioned historic or regional names for our instrument.
Whether Dan intended it or not, I consider him to have spearheaded a movement where now it seems to be pretty much standard procedure to refer to traditional mountain dulcimers as 'dulcimores'. Since it's handy to use as a shorter name than constantly saying or writing 'traditional dulcimer', and has a lilting quality, I'm all for making things simpler when discussing our favorite instrument. But I do think that Dan deserves the credit for 'reviving' the name 'dulcimore' into now common usage and understanding.
Those irritated by grain of sand best avoid beach.
-Strumelia proverb c.1990