Persnicketiness definition of persnicketiness by The Free Persnickety sense is reasonably elusive. It refers to someone who is extremely choosy and critical. A persnickety individual frequently pay strict attention to detail and has high standards when it comes to standards and flawlessness. Their fastidious nature can be perceived as commendable, but it can also exacerbate unwarranted censure and avoidable dissatisfaction. Being persnickety is typically connected with detailed attention to detail but can also be seen as a form of perfectionism.