unprofessional (adj.)

• amateur
• amateurish
• everyday
• improper
• incompetent
• inefficient
• inexperienced
• inexpert
• inferior
• lax
• lay
• negligent
• ordinary
• poor
• second-rate
• semiskilled
• shoddy
• sloppy
• unbecoming
• unbefitting
• understandable
• undignified
• unendowed
• unethical
• unfinished
• unfitting
• uninitiated
• unpolished
• unprepared
• unprincipled
• unscholarly
• unschooled
• unseemly
• unskilled
• untalented
• untaught
• untrained
• untutored
• unworthy