plumber's helper

plumber's snake

poitrine d'agneau

poor man's orchid

poor man's pulse

poor man's weatherglass

pope's nose

porter's beer

potter's clay

potter's earth

potter's field

potter's wheel

pott's disease

prairie bird's-foot trefoil

presidents' day

prince albert's yew

prince-of-wales'-heath

prince's-feather

prince's pine

prince's-plume

printer's devil

printer's ink

prisoner's base

prompter's box

przevalski's horse

przewalski's horse

pull in one's horns

pull one's weight

pull someone's leg

pull the wool over someone's eyes

purkinje's system

purkinje's tissue

purple virgin's bower

pussy's-paw

quai d'orsay

queckenstedt's test

queen anne's lace

queen's counsel

queen's crape myrtle

queen's cup

queen's english

quincke's edema

rabbit's-foot fern

ragpicker's disease

ragsorter's disease

raison d'etre

ram's-head

ram's-head lady's slipper

ram's horn

ranvier's nodes

rat's-tail cactus

rattlesnake's master

raynaud's sign

reach one's nostrils

recurring'A=0

red angel's trumpet

red bird's eye

reiter's disease

reiter's syndrome

republic of cote d'ivoire

revolutionary people's liberation front

revolutionary people's liberation party

revolutionary people's struggle

reye's syndrome

richard d'oyly carte

richardson's geranium

riggs' disease

ringer's solution

robert e lee's birthday

robert's rules of order

robin's plantain

rock 'n' roll

rock'n'roll

rock 'n' roll musician

rogue's gallery

rolando's area

rolando's fissure

rugel's plantain