After wasting too many hours of my life, I think that I have the correct answer. The first word that I found was "waterfall". I saw the 'wat' and the only word that I knew that began with 'wat' was water. The second word I got was "dragonfly". I saw 'fly' and knew that it had to be a word that ended in 'fly'. I slowly went through them all. (housefly, mayfly, ruffly, butterfly, dragonfly, horsefly) I then went through them and dragonfly was the only 9 letter word that worked. I also got the word "head" pretty quickly after seeing 'hea' and making the connection to 'head'.

• wat + erf + all = waterfall
• dra + gon + fly = dragonfly
• hea + dli + ght = headlight

I got stuck for along time when I made the word "permanent". Which I later realized that even though it worked, it wasn't part of the answer.

per + man + ent = permanent

After realzing that, I managed to solver several more words:

• fis + her + man = fisherman
• dif + fer + ent = different
• new + spa + per = newspaper

I only had 4 words left, but they were some of the hardest:

• ove + rbo + ard = overboard
• con + duc + tor = conductor
• hai + rbr + ush = hairbrush
• ban + dst + and = bandstand

One thing that stumped me was that I didn't realize bandstand was a word, and I also mistakenly thought that hairbrush was two words or had a hyphen. It was a fun puzzle, but it took several hours and I used a ton of paper. The last word I solved was "conductor" and it was a relief. I used a lot of trial & error, but some words also popped out at me. I also made lots of connections like

rbr + ush = r brush
dst + and = d stand
spa + per + s paper
fis + her = fisher