[Details] A overlaps B tests if part of their respective interiors intersect, and if this intersection is the same dimension as the interiors of the original geometries. (This last bit rules out crosses). Some of their interior MUST intersect with the exterior of the other one and vice versa (i.e., one cannot be within the other). This bit rules out within and contains. Overlap only applies if the two geometries are of the same dimension. [Name] 
overlaps
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d i s j o i n t
i n t e r s e c t s
c r o s s e s
o v e r l a p s
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c o n t a i n s
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