(n) rock wool
(P)
(n) locknut
(n) rockfill
(n) overlock sewing machine (wasei: lock machine)
(n) (comp) lossy compression
(n) Rochelle salt
(n) Roche limit
Roche's limit (closest that a natural satellite can come to the center of a planet without disintegrating due to tidal forces)
(n) sold out (wasei: lot up)
out of production
(n) Rotring (pen)
(n) lobbying
(n) ropivacaine (local anaesthetic)
(n) loft jazz
(n) robotics
(n) robotics
(n) robotology
(n) Romany (language)
(n) Romansch (language)
(n) romance car
deluxe train
(n) (abbr) romanticist
(adj-na,n) romantic
(P)
(n) Romantic music
(n) game cartridge (wasei: ROM cassette)
(n) (1) royalty
(2) loyalty
(n) roller conveyor
roller way
roller path
(n) long stay
(n) long seller
(P)
(n) long dress
(n) long hit
(n) Longbeach
(P)
(n) long boots