There are 1,139 eight-letter words with "p" as the fourth letter in the Scrabble dictionary. I trust 150 of the more common ones will suffice:
adoption
adoptive
airplane
anyplace
apoplexy
atypical
auspices
bespoken
campaign
campfire
campsite
chaperon
chaplain
chipmunk
claptrap
clippers
clipping
compiler
complain
complete
composed
composer
compound
compress
comprise
computer
corporal
coupling
crippled
culpable
dampness
deepness
despatch
despotic
dispatch
dispense
disperse
dispirit
displace
disposal
disprove
dumpling
Dumpster
earphone
eggplant
Egyptian
elephant
Epiphany
eruption
esophagi
eyepiece
flapjack
flippant
flypaper
frippery
graphics
graphite
gumption
gunpoint
helpless
helpmate
Hispanic
hospital
humpback
jeopardy
jumpsuit
keepsake
keypunch
knapsack
lamppost
leapfrog
limpidly
limpness
loophole
manpower
midpoint
misplace
misprint
morpheme
morphine
neophyte
neoprene
palpable
palpably
pamphlet
peephole
pinpoint
pinprick
porphyry
porpoise
properly
property
prophecy
prophesy
proposal
propound
puppetry
purplish
reappear
respects
response
rhapsody
sapphire
seaplane
shepherd
shipmate
shipment
shipping
shipyard
shoplift
shoptalk
shopworn
simplify
slapdash
slipknot
slippage
slippery
slipshod
sloppily
snappish
snapshot
soapsuds
stopcock
stopover
stoppage
stupidly
subpoena
supplant
supplier
supplies
supposed
suppress
surplice
surprise
suspense
sympathy
symphony
symposia
taxpayer
tempered
template
temporal
tempting
trapdoor
triptych
tropical
tympanum
unopened
unspoken
weaponry
whiplash
whipping
whopping
wrapping
zeppelin
According to SOWPODS (the combination of Scrabble dictionaries used around the world) there are 8 words with the pattern ---PPI-. That is, seven letter words with 4th letter P and 5th letter P and 6th letter I. In alphabetical order, they are: chappie chippie clippie crappie croppie drappie preppie shippie
According to SOWPODS (the combination of Scrabble dictionaries used around the world) there are 8 words with the pattern --PPA. That is, five letter words with 3rd letter P and 4th letter P and 5th letter A. In alphabetical order, they are: cuppa kappa kippa koppa nappa poppa tappa zoppa
According to SOWPODS (the combination of Scrabble dictionaries used around the world) there are 8 words with the pattern P--PY. That is, five letter words with 1st letter P and 4th letter P and 5th letter Y. In alphabetical order, they are: pappy paspy peppy pippy poppy pulpy puppy purpy
According to SOWPODS (the combination of Scrabble dictionaries used around the world) there are 8 words with the pattern --POP----. That is, nine letter words with 3rd letter P and 4th letter O and 5th letter P. In alphabetical order, they are: hypophyge hypoploid hypopneas hypopneic hypopnoea hypopyons lipoplast unpopular
According to SOWPODS (the combination of Scrabble dictionaries used around the world) there are 8 words with the pattern P-EP-I--. That is, eight letter words with 1st letter P and 3rd letter E and 4th letter P and 6th letter I. In alphabetical order, they are: preppier preppies preppily prepping preprice preprint psephism psephite
According to SOWPODS (the combination of Scrabble dictionaries used around the world) there are 8 words with the pattern --AN---P-. That is, nine letter words with 3rd letter A and 4th letter N and 8th letter P. In alphabetical order, they are: changeups clanships cyanotype deanships grandpapa standpipe tranships transumpt
According to SOWPODS (the combination of Scrabble dictionaries used around the world) there are 8 words with the pattern P--AN. That is, five letter words with 1st letter P and 4th letter A and 5th letter N. In alphabetical order, they are: paean pagan pavan pecan pekan powan pucan pyran
According to SOWPODS (the combination of Scrabble dictionaries used around the world) there are 8 words with the pattern P--IN. That is, five letter words with 1st letter P and 4th letter I and 5th letter N. In alphabetical order, they are: patin pavin pekin plain potin powin proin purin
According to SOWPODS (the combination of Scrabble dictionaries used around the world) there are 1 words with the pattern P--I--P-. That is, eight letter words with 1st letter P and 4th letter I and 7th letter P. In alphabetical order, they are: pericope
According to SOWPODS (the combination of Scrabble dictionaries used around the world) there are 1 words with the pattern -P-P--A--. That is, nine letter words with 2nd letter P and 4th letter P and 7th letter A. In alphabetical order, they are: epiphragm
According to SOWPODS (the combination of Scrabble dictionaries used around the world) there are 8 words with the pattern -LAPP--. That is, seven letter words with 2nd letter L and 3rd letter A and 4th letter P and 5th letter P. In alphabetical order, they are: clapped clapper flapped flapper klapped plapped slapped slapper
According to SOWPODS (the combination of Scrabble dictionaries used around the world) there are 8 words with the pattern SAPP---. That is, seven letter words with 1st letter S and 2nd letter A and 3rd letter P and 4th letter P. In alphabetical order, they are: sappans sappers sapphic sappier sappily sapping sappled sapples