Which phrase best represents a situation where a position is available but not filled?

A job vacancy accurately represents a situation where a position is available but not filled. This term specifically denotes that there is an open role within an organization that has not yet been occupied by an employee. It conveys the idea that the company is actively looking for someone to fill this position, which could involve recruiting efforts and the creation of job postings.

In contrast, role assignment and work assignment imply that individuals have been given specific roles or tasks to carry out, suggesting those positions are already filled. The term "position likely" is vague and does not clearly communicate whether a job is available or if it is simply anticipated to be open in the future. Thus, job vacancy is the most precise and widely understood phrase to describe an unoccupied position within a workplace.