1. On a railway flatcar
   - piggyback, pig-a-back 
2. On the back or shoulder or astraddle on the hip
   - piggyback, pig-a-back

Encyclopedia: Pickaback

• recreation room
• recreational
• recreational drug
• recreational facility
• recreational vehicle
• recreative
• recriminate
• recrimination
• recriminative
• recriminatory
• recross
• recrudesce
• recrudescence
• recrudescent
• recruit
• recruiter
• recruiting-sergeant
• recruitment
• recrystallisation
• recrystallization
• rectal
• rectal artery
• rectal reflex
• rectal vein
• rectangle