The definition of across is on the other side or from the other side.(adverb)
To walk over a bridge is an example of to walk across.
Across is defined as from one side to the other.(preposition)
Houses on opposite sides of the street is an example of across.
See across in Webster's New World College Dictionary
Origin: ME acros < a-, on, in + cros, cross, after Anglo-Fr an croix
See across in American Heritage Dictionary 4
Origin: Middle English acrois
Origin: , from Anglo-Norman an croiz
Origin: : an, in (from Latin in; see in-2)
Origin: + croiz, cross (from Latin crux; see Cross ).
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