solus

adjective
  1. Alone; by oneself; used to indicate that someone is alone or unaccompanied. adjective
    He walked solus through the quiet streets, lost in thought.
    The artist preferred to work solus, finding inspiration in solitude.
  2. In law, used to describe a situation where a person is acting alone, without any partners or associates. adjective
    The lawyer argued that his client was solus in the decision-making process.
    In the contract, it was specified that the party acted solus, without any external influence.