jet bridge vs pedestrian bridge

jet bridge and pedestrian bridge both are nouns.

Word	Noun	Adjective	Verb	Adverb
jet bridge	Yes	No	No	No
pedestrian bridge	Yes	No	No	No

As nouns, pedestrian bridge is a hypernym of jet bridge; that is, pedestrian bridge is a word with a broader meaning than jet bridge:

jet bridge: an extendible bridge for loading passengers onto large commercial airplanes; provides protected access to the plane from the gate
pedestrian bridge: a bridge designed for pedestrians

Other hypernyms of jet bridge include footbridge, overcrossing.

jet bridge (noun)	pedestrian bridge (noun)
an extendible bridge for loading passengers onto large commercial airplanes; provides protected access to the plane from the gate	a bridge designed for pedestrians