A solid-weight icon from Font Awesome, a free web icon font, depicting a Venus symbol (a female symbol) and a Mars symbol (a male symbol) with one placed on top of the other.
The visual relationship between the two circles in this diagram is idiosyncratic (and arguably incorrect) for a heterosexuality symbol.  For an indisputably correct version of the heterosexuality symbol using overall similar visual techniques, see File:HeteroSym-monochrome interlaced with thick strokes.svg
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