The initial idioms of the letter R

respiratory infection	respiratory organ
respiratory quotient	respiratory rate
respiratory syncytial virus	respiratory system
respiratory tract	respiratory tract infection
respire	respite
resplend	resplendence
resplendency	resplendent
resplendent quetzel	resplendent trogon
resplendently	respond
respondent	responder
response	response time
responsibility	responsible
responsible for	responsibleness
responsibly	responsive
responsiveness	rest