protrusion; projecting part; bulge; overhang
Technical term for a part that sticks out from a surface or structure. Used in engineering, architecture, and physical descriptions.
Please be careful of the protruding part of this machine.
The overhang of the building juts out over the sidewalk.
出っ張り is a colloquial term for a bulge or protrusion, while 突出部 is formal and technical.
kern
Compound of 突出 (とっしゅつ, 'protrusion') + 部 (ぶ, 'part'). The reading とっしゅつ is the on'yomi of 突出, and 部 is a common suffix for parts or sections.