The story
Originally bull-dozer (1875, Louisiana, US), in the bullier and terrorizer sense; bulldoze + -er. The name for the earthmoving machine came later, figuratively, from that sense.
Etymology from Wiktionary, CC BY-SA 4.0.
bulldozer
Today it means: A tractor with caterpillar tracks and an attached blade for pushing earth and building debris for coarse preliminary surface grading, demolishing building structures, etc. Full definition →