Denshi Jisho — Online Japanese dictionary

氾濫 はんらん overflowing; flood
Common word, Noun, Suru verb 
広がる ひろがる to spread (out); to extend; to stretch; to reach to; to get around; to fill (e.g. a space)
Common word, Godan verb with ru ending, Intransitive verb 
拡がる ひろがる to spread (out); to extend; to stretch; to reach to; to get around; to fill (e.g. a space)
Godan verb with ru ending, Intransitive verb 

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