Meaning

adjective primarily temporal sense; being or indicating a relatively great or greater than average duration or passage of time or a duration as specified

adjective primarily spatial sense; of relatively great or greater than average spatial extension or extension as specified

adjective of relatively great height; - Sherwood Anderson

originEtymology tree English long Proto-Indo-European *-yōs Proto-Indo-European *-tHós Proto-Indo-European *-istHos Proto-Germanic *-istaz Proto-West Germanic *-ist Old English -est Middle English -est English -est English longest From long + -est.

Etymology from Wiktionary, CC BY-SA 3.0