It is a chemical ester. Its name is propyl ethanoate(acetate).
It is correctly written as ; -
CH3COOCH2CH2CH3
Note the use os CAPITAL letter, as for all elements.
Its ester structure is
CH3- C(=O)-O-CH2-CH2-CH3
It can be made in the lab. by refluxing ethanoic acid and propan-1-ol, in the presence of a little sulphuric acid to act as an activator.