Where does “bisector” come from?

Bisector comes from English bisect, from Latin bis meaning twice, ultimately from Proto-Indo-European dwóh₁ meaning two.

bisector (English): A line or curve that bisects or divides a line...

Definitions

  1. A line or curve that bisects or divides a line...

Ancestry of “bisector”, step by step

bisector traces back through 3 separate lines of ancestry.

via English bisect

StepLanguageWordMeaning
1EnglishbisectTo cut or divide into two parts; A bisector,...
2Frenchbissexteleap day
3Latinbisextusintercalary day
4Latinbistwice, two times, on two occasions, in two ways
5Latincolorcolour, shade; color; pigment; complexion
6Ancient Greekμέτρονsomething used to measure: measure, rule, weight;...
7Ancient Greek-τρονForms instrument nouns
8Proto-Hellenic-tronForms instrument nouns from verb stems
9Proto-Indo-European-tromForms nouns denoting a tool or instrument
10Proto-Indo-European-tḗrDerives agent nouns from verbs, denoting someone...

via English ‐or

StepLanguageWordMeaning
1English‐orCreates an agent noun, often from a verb, indicating a person or object (often machines or parts of them) that do the verb or part of speech with which they are formed
2Middle English-our
3Old French-eorAlternative form of -or
4Latin-ator-ator, -er; second-person singular future passive...
5Latin-tor-er
6Proto-Italic-tōrForms agent nouns to verb stems
7Proto-Indo-European-tōrDerives agent nouns from verbs, denoting someone...
8Proto-Indo-European-tor-s

via French bissecteur

StepLanguageWordMeaning
1Frenchbissecteurbisecting
2Frenchsecteursector; area, vicinity
3LatinsectorOne who cuts or cuts off, cutter; A purchaser or...
4Proto-Italicsekʷōrfollow, come/go after
5Proto-Indo-Europeansékʷetorto be following
6Proto-Indo-Europeansekʷ-to follow; to see; to say
Every word from Proto-Indo-European -tḗr
bisector — Etymology, Origin & Word History | Etymology Explorer