马大哈 (馬大哈) mǎdàhā

mǎdàhā noun a careless person; scatterbrain; frivolous and forgetful
Domain: Modern Chinese 现代汉语
Notes: Abbreviation for 马马虎虎、大大咧咧、嘻嘻哈哈 (CC-CEDICT '馬大哈')