Denshi Jisho — Online Japanese dictionary

である to be (formal, literary)
Godan verb with ru ending (irregular verb) 
出歩く である to go out; to take a stroll; to go about
Godan verb with ku ending, Intransitive verb 
であるから therefore; and so; for that reason; accordingly; consequently; hence
Expression 
であるからして therefore; and so; for that reason; accordingly; consequently; hence
Expression 
である であるたい literary form imparting a formal written nuance (with sentences ending in "de aru")
Noun 

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