Nouns

(n)piggybackthe act of carrying something piggyback

Verbs

(v)piggybackride on someone's shoulders or back
(v)piggybackhaul truck trailers loaded with commodities on railroad cars
(v)piggybackhaul by railroad car
(v)piggybacksupport on the back and shoulders“He piggybacked her child so she could see the show”
(v)piggybackbring into alignment with“an amendment to piggyback the current law”

Adverbs

(r)piggyback, pickaback, pig-a-backon a railroad flatcar“the trailer rode piggyback across the country”
(r)piggyback, pickaback, pig-a-backon the back or shoulder or astraddle on the hip“she carried her child piggyback”