rate - spleen
raté - past participle of rater (to fail, miss)

relâche - rest, respite
relâché - loose, lax

reste - rest, leftover
resté - past participle of rester (to stay)

retraite - retreat, retirement
retraité - retired person; past participle of retraiter (to reprocess)

rot - belch, burp
rôt - (archaic) roast

roue - wheel
roué - (adj) cunning, sly; un roué - cunning/sly person; past participle of rouer (to beat/thrash)