Denshi Jisho — Online Japanese dictionary

ざっと roughly; in round numbers
Common word, Adverb, Onomatopoeic or mimetic word 
雑踏 ざっと congestion; traffic jam; throng; hustle and bustle
Common word, Noun, Suru verb 
雑沓 ざっと congestion; traffic jam; throng; hustle and bustle
Noun, Suru verb 
雑鬧 ざっと congestion; traffic jam; throng; hustle and bustle
Noun, Suru verb 

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