What term is used to describe a person who works alongside you?

The term "Co-Worker" specifically refers to someone who works in the same organization or environment as you and is actively involved in the same workplace. This can include individuals who may not be in the same department but share common goals and contribute collectively to the organization’s objectives. In this context, "Co-Worker" emphasizes the collaborative aspect of the work relationship, highlighting the idea that you are part of a team or workforce together, regardless of job titles or duties.

While the other terms also relate to the concept of working with others, "Colleague" often implies a more formal professional relationship, typically referring to individuals who hold similar positions or ranks within the workplace. "Associate" can denote a broader range of relationships, often in a professional or business context that does not necessarily imply an immediate work environment. "Peer" might suggest individuals at the same level or status but does not uniquely imply a work setting, as it can refer to social relations as well. Hence, "Co-Worker" is the most direct and relevant term to describe someone who works alongside you in the same environment.