According to SOWPODS (the combination of Scrabble dictionaries
used around the world) there are 16 words with the pattern
---AP-IN-. That is, nine letter words with 4th letter A and 5th
letter P and 7th letter I and 8th letter N. In alphabetical order,
they are:
becapping
delapsing
illapsing
paraphing
recapping
relapsing
remapping
scrapping
seraphine
seraphins
steapsins
strapline
strapping
synapsing
talapoins
uncapping