"Definitions Change with time, economies change with space." Add these two proverbs together and we can come to conceptualize economic geography.
Economic Geography essentially deals with the relationship between the economy and space. It focuses on different economic sectors on different scales, the changes over different time periods and the effects of economic activities on space (in terms on environmental, political, technological and yes, economic!!).
Another way to look at the definition of economic geography is to break down 'Economic Geography' and produce almost a mathmatical representation in a word formula. Therefore:
GEOGRAPHY + ECONOMICS + ½(NATURAL + SOCIAL SCIENCES) = ECONOMIC GEOGRAPHY
We can clarify that Economics is defined as:
However, not all aspects of economics concern geography since geography is the science of space and doesn't need to get involved with topics such as (yawn!) accountancy. Therefore, geography only alligns itself with the spatial context of economics.