the.com/protrusion

Something that stuck its neck out and never pulled it back in.

means A part that sticks out beyond the surrounding surface or line.

from From Latin protrudere — pro ('forward') plus trudere ('to thrust, push') — the same trudere that gives English 'intrude' and 'extrude.' A protrusion is literally something that got pushed forward and stayed there.

etymology
Latin protrudere, to thrust forward
geology use
describes magma pushing through earth's crust
medical flag
disc protrusion means bulge, not full rupture
everyday truth
anything that sticks out qualifies, no drama needed
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