horizontal
hor·i·zon·tal
adj \ˌhȯr-ə-ˈzänt-əl, ˌhär-\Definition of HORIZONTAL
1
: relating to or being a transverse plane or section of the body
2
: relating to or being transmission (as of a disease) by physical contact or proximity in contrast with inheritance—compare vertical
—hor·i·zon·tal·ly \-əl-ē\ (audio pronunciation) adverb
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