trad ‧ ing /ˈtreɪdɪŋ/ BrE AmE noun [uncountable]
[ Word Family: noun : ↑ trade , ↑ trader , ↑ trading ; verb : ↑ trade ]
1 . the activity of buying and selling goods or services
Sunday trading British English (=shops being open on Sunday)
2 . the activity of buying and selling ↑ stock s etc
heavy/light trading (=a lot of trading or a little trading)
Shares dropped 10% in heavy trading.