R as in …

Rabbi

Rabbit

Race

Racist

Rack

Rag

Rain

Rainbow

Raise

Raisin

Ramp

Randomness

Rank

Rap

Rape

Rapist

Rating

Rave

Re

Reach

Reaction

Read

Reader

Ready

Real

Realisation

Realization

Rear

Reason

Receiver

Recent

Reception

Record

Red

Redneck

Refrigerator

Register

Relationship

Religion

Religious

Remembering

Reminder

Remove

Report

Reptile

Respect

Respondent

Rest

Restaurant

Result

Retail

Retail Store

Retardation

Return

Rex

Rhyme

Rib

Rice

Rich

Ride

Right

Ring

Rip

Risk

River

Road

Roast

Robber

Robert

Robin

Robot

Rock

Rogue

Roll

Roller

Roman

Roof

Room

Rope

Rose

Round

Round Table

Rub

Rubber

Ruin

Rule

Run

Rune

Russia

Russian