180 Elbow

Fitness/Anatomy: A chart showing a 180-degree elbow extension (full range of motion of the arm).

Engineering/Plumbing: A chart for 180-degree pipe elbows, typically used in piping systems—showing dimensions, materials, pressure ratings, etc.

Data Analysis (Elbow Method): An “elbow chart” used in machine learning or clustering analysis, perhaps referring to a point at which the curve bends at 180 degrees (although that’s unusual, as elbows are typically more acute).