# strophoid

[strof-oid, stroh-foid]

- a plane curve generated by the loci of points p and pprime; on a straight line that intersects the y-axis at a point n and the minus x-axis at a fixed point q, such that pn = npprime; = on, as on changes, where o is the origin. Equation: y2 = x2(x+a)/(a−x).

## Origin of strophoid^{}

Dictionary.com Unabridged
Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

# strophoid

[strō′foid′]

- The curve traced out by points P and P′ which lie on lines through a fixed point A where the midpoint M of PP′ is on a fixed line and the absolute value |;PM|; equals the absolute value |;P′M|; equals the absolute value |;MO|;, where O is the projection of A onto that fixed line.

The American Heritage® Science Dictionary
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