sole
adjective [ before noun ]
uk/səʊl/ usbeing the only one:
Investment trusts are companies whose sole business is investing.
sole owner/director A company which has a sole director is required to have another person as its company secretary.
The deal makes the bank the company's sole agent in the region.
The University is North America's sole supplier of an antibiotic to treat tuberculosis.
not shared with anyone else:
UK employers are far too powerful to accept sole responsibility for employees' pensions.