Amateurish, unprofessional, unpolished, juvenile.
Of inferior quality.
A professional sports association at the lower levels of minor league organization.
A low-ranking or inferior level among groups, professions, organizations, etc.
Cowardly, uncourageous; lacking character.
Lacking a backbone; without vertebrae.
A spineless person; a coward.
An animal without vertebrae, i.e. backbone.