rīvus, a brook: rivulet; through Fr., rival, de-rive, derivation. (For river and arrive see [ripa]).
rog-o (rŏgāt-), I ask: ar-rogant, ab-rogate, interrogation, de-rogatory, (Fr.).
rŏta, a wheel; rŏt-ula, dimin.; rŏt-undus, round: rot-ary, rotate, rotunda, Fr., roll, rowel, roulette (all from rotula), roué, round.
rumpĕre, to break; ruptus, broken: rupture (Fr.), ab-rupt, e-rupt-ive, dis-ruption, bank-rupt (bank = bench, table of money changer); through Fr., rout (lit. a division), route and rut (= a path).
Săcer (săcr-), sacred; sacr-āre, sanc-īre, consecrate: sacrifice, sacrilege, sacerdotal, sacrament, de-secration, sanctity, sanctuary, saint (Fr.).
sal, salt: salary (i.e., salt-money), saliferous; through Fr., saline, salad, sauce (= salsus, salted).
săli-o (sălt-), I leap (-silio, -sult-, in compounds): sali-ent, re-sili-ent, ex-ultant, saltation, in-sult, de-sultory; through Fr., sally, assail, assault.
salv-us, safe; sălus (sălūt-), health, greeting: salubrious, salute; through Fr., salvation, salvage, save, salutary, saviour (Lat. salvator).
sānus, sound; sān-āre (sānāt-), to heal: sane, sanitary, sanatorium.