cod ‧ ing AC /ˈkəʊdɪŋ $ ˈkoʊ-/ BrE AmE noun [uncountable]
[ Word Family: noun : ↑ code , ↑ coding ; verb : ↑ code ; adjective : ↑ coded ]
a system of marking something with letters, symbols etc so that facts about it can be understood by someone who knows the system:
Most petrol stations use colour coding for different types of petrol.
A coding system is used to record what is found and when.