Synonyms of amateurish

2 Syllables
awkward, bungling, klutzy, inept
3 Syllables
untrained, insipid, nonexpert, inexpert, unskilled, unworked, unmilled, unskillful, bush-league, unfitted
4 Syllables
unfinished, unprocessed, unmatured, incompetent, unfulfilled, unassembled
5 Syllables
unprofessional, inexperienced