- raceme, racimo
- racemose, racemoso
- rachilla, raquilla
- rachis, raquis
- radiate, radiado
- radical, radical
- radicant, radicante
- radicle, radícula
- rain forest, selva alta perennifolia
- rain-loving, ombrófilo
- raised, elevado
- ramal, rameal
- rame, ramilla
- rament, ramento
- ramentaceous, ramentáceo, ramentoso
- rameous, rameal
- ramificate, ramificarse
- ramose, ramificado
- rank, serie
- raphe, rafe
- raphides, rafidios
- raquilla, raquilla
- rarely, raramente
- ravine, barranca
- ray, rayo
- raylets, rayuelos
- readily, prontamente
- receptacle, receptáculo
- receptacular bractlets, bractéolas receptaculares
- reclinate, reclinado
- reclining, reclinado
- rectangular, rectangular
- recurvate, recurvado, recorvado, decurvado
- recurved, recurvado
- reddish, rojizo
- reduced, reducido
- reduplicate, reduplicado
- reed, caña
- reflexed, reflexo
- regular flower, flor regular
- relic, relicto
- relict, relicto
- remote, remoto
- reniform, reniforme
- repand, repando
- repent, rastrero
- replicate, replicado
- replum, replo
- resinous, resinoso
- resupinate, resupinado
- reticular, reticulado
- reticulate, reticulado
- retinaculum, retináculo
- retrorse, retrorso
- retrorsely, retro-
- retrorsely barbellate, retrobarbado
- retrorsely crenate, retro-crenado
- retrorsely serrate, retro-serrado
- retuse, retuso
- revolute, revoluto
- rhipidium, ripidio
- rhizocarpic, rizocárpico
- rhizoid, rizoide
- rhizomatous, rizomatoso
- rhizome, rizoma
- rhizophore, rizóforo
- rhombate, rómbico
- rhombic, rómbico
- rhomboid, romboide
- rhomboidal, rómbico
- rib, costilla
- ribbed, acostillado, costato, costillado
- ridge, cresta, costilla
- ridged, estriado
- rim, borde
- rima, rímula
- ringed, anillado
- ringent, ringente
- ringlike, anular
- riparian, ripario
- riverside, ripario
- roadside, borde de camino
- robust, robusto
- rolled, enrollado
- root, raíz
- root thorns, espinas radicales
- rooting, enraizando
- rootstock, órgano subterráneo
- rosette, roseta
- rosetted, arrosetado
- rostellum, rostelo
- rostrate, rostrado
- rostrum, rostro
- rosulate, arrosetado
- rotate, rotáceo
- rotund-, rotundi-
- rotundate, redondeado
- rotundifolious, rotundifolio
- rounded, redondeado
- roundly, redondeadamente
- rudiment, rudimento
- rudimentary, rudimentario
- rufous, rojo-pardusco
- rugose, rugoso
- rugulate, rugulado
- rugulose, ruguloso
- ruminate, ruminado
- runcinate, runcinado
- runner, estolón
- rupicolous, rupícola
- ruptile, rúptil
- rush-like, juncoide
- rusty, ferrugíneo