challenge
noun
uk/ˈtʃælɪndʒ/ us [ C or U ]
a job, duty, or situation that is difficult because you must use a lot of effort, determination, and skill in order to be successful:
accept/face/meet a challenge After significant losses last year, the company now faces the challenge of trying to repair its reputation with investors.
be/pose/present a challenge The weakness of the dollar could pose a challenge to the company's expansion plans.
As a software developer he enjoys the challenge of working with cutting-edge technology.
She was getting bored at work and felt she needed a new challenge.
Finding time to do the work has proven a real challenge.
a big/major/serious challenge
[ C ]
an invitation for someone to compete against you or for you to prove that you can achieve a particular goal:
challenge from sb Responding to a challenge from dissident shareholders, the board approved a number of steps to enhance shareholder value.
[ C ]
an act of asking whether something is true or legal, or whether someone has the authority or right to do something:
mount/launch a challenge against Unions are planning to launch a legal challenge against the airline for changing the work schedules of 14,000 cabin crew.
challenge
verb [ T ]
uk/ˈtʃælɪndʒ/ usto officially question whether something is true or legal, or whether someone has the authority or right to do something:
Keep copies of all written correspondence to support your case if the company later challenges you for further payment.
Corporate lawyers challenged the ban, but the court upheld it last year.
to compete against someone or ask them to prove that they can achieve a particular goal:
challenge sb to do sth Consumers are challenging manufacturers to adopt greener policies.
to encourage someone to increase their skills, determination, abilities, etc. by making them do something new or difficult:
People are just looking for jobs that will challenge and inspire them.
to cause difficulties for someone or something:
Local businesses have been greatly challenged by the recession.