A usual convention in topology is to have *arc* mean *path in a space which also is a homeomorphism onto its image.* This is simultaneously a *felicity *and a* hazardousness **infelicity. *

It is a hazardousness in that in combinatorics it is absolutely standard to have *path *signal that *no repetitions whatsoever are allowed, *while in topology *path* tends to signal that *self-intersections are allowed. *It is a *felicity* in that it is absolutely standard to call the edges of (abstract) *digraphs* by the name *arc*, and it is usual to *formalize embedded directed graphs *(embedded in some space or the other, e.g. in to get *plane digraph, *or in to get *hyperbolic digraphs*) by *arcs* in the usual topological, self-intersections-forbidden sense of the word. So in *that* sense, *arc *and *arc* correspond *felicitously*.

( And by the way, although we defined the term *hazardousness *classically, by letting *hazardousness * *in**f**elicity, *we have just seen, by example, that it is not true that [hazardousness felicity ]. Fully spelled out

[infelicity felicity ]

To sum up, there are terms which are simultaneously a *hazardousness* and a *felicity. **Phew.
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