Lackadaisical adjective formal
Nobody wants to teach a lackadaisical student.
There were times Peter seemed a little lackadaisical.
Due to the lackadaisical attitude of a number of employees, the quality of the company's customer service has significantly decreased.
To be satisfied with past achievements and stop trying to achieve something new..
Adequate measures or actions
Enthusiasm and perseverance
Lackadaisical may now be a single word. However, its original form derived from a phrase, 'alack a day' or 'alack the day' which originally meant “Shame or reproach to the day!”. At some point in the eighteenth century, the form lackadaisy appeared, with lackadaisical coming along shortly afterwards for somebody who regularly used the cry. At first it meant that the person was feebly sentimental rather than lazy, but then it was used to espress the idea of somebody who was affectedly languishing, and thence to someone merely lazy.
Used to allude that the last force, problem or burden which is seemingly minor and small causes a person, system or organisation to collapse or fail
Her husband's violent act last night was the straw that broke the donkey's back and she left him