Model GST Law
Business is defined in Section 2(17) of Model GST Law but there is no definition of Profession :-
(17) “business” includes –
(a) any trade, commerce, manufacture, profession, vocation or any other similar activity, whether or not it is for a pecuniary benefit;
(b) any transaction in connection with or incidental or ancillary to (a) above;
(c) any transaction in the nature of (a) above, whether or not there is volume, frequency, continuity or regularity of such transaction;
(d) supply or acquisition of goods including capital assets and services in connection with commencement or closure of business;
(e) provision by a club, association, society, or any such body (for a subscription or any other consideration) of the facilities or benefits to its members, as the case may be;
(f) admission, for a consideration, of persons to any premises; and
(g) services supplied by a person as the holder of an office which has been accepted by him in the course or furtherance of his trade, profession or vocation;