In the United States, teacher is the usual word for someone teaching pre-K through high school, professor commonly refers to a college or university faculty member, and instructor is a broad term that may be an official academic title or describe someone teaching a course, workshop, or skill.
The words overlap, but titles and preferences vary by institution.
When do Americans say “teacher”?
Americans normally call an elementary-, middle-, or high-school educator a teacher:
"My son's math teacher emailed us."
"She was a high-school teacher before moving into corporate training."
At a college, students may casually say teacher, especially when speaking generally. However, addressing a university faculty member as Teacher Smith would sound unusual in most U.S. settings.
When do Americans say “professor”?
Professor is commonly used for someone who teaches at a college or university. It can also be a formal academic rank, as in assistant professor, associate professor, or professor.
That creates an important distinction: a student may politely address a college instructor as Professor Lee, even when the person's official appointment is not the rank of full professor. Practices vary by campus and department.
If the person has stated a preference, follow it:
"Please call me Dr. Lee."
"Professor Lee is fine."
Do not assume that every professor has a doctorate or that everyone with a doctorate is a professor.
What does “instructor” mean?
Instructor focuses on the teaching role. In higher education, it may be an official job title with institution-specific responsibilities. EducationUSA includes instructors among the people who may form college or university faculty.
Outside universities, instructor is common for skills-based learning:
- driving instructor
- fitness instructor
- flight instructor
- corporate-training instructor
- workshop instructor
In workplace learning, facilitator, trainer, coach, and instructor can describe different methods or official roles. Do not assume they are interchangeable in every organization.
What might you hear at work?
"My professor connected me with this internship."
The speaker is probably referring to a college or university educator.
"I need to attend a parent-teacher conference."
This is a meeting between a school and a student's parent or guardian, usually in K–12 education.
A lot to take in? It is.
But Rome wasn't built in a day. Build your American workplace English one expression and cultural reference at a time—with curated explanations and structured practice in Lyra Practice.
Start a session →"The instructor will send the course materials tomorrow."
This could refer to a university class, company workshop, certification course, or other training.
"She joined us from the faculty of a business school."
Here faculty means the academic teaching staff or, depending on the international context, an academic division. U.S. listeners may need clarification.
"He is an adjunct professor."
Adjunct generally indicates a non-tenure-track, often part-time teaching appointment, but employment terms vary substantially by institution.
What can you say naturally?
For workplace small talk:
"I used to teach high-school science."
For networking:
"One of my university professors introduced me to the field."
For training:
"The instructor has ten years of experience in cloud security."
If you are unsure how to address someone:
"How would you prefer to be addressed?"
In an email, you can also use the title shown in the person's signature, faculty profile, or course materials. Dr. is appropriate for someone who uses that title, but it is not a universal replacement for Professor.
What should you put on a résumé?
Use the title that accurately reflects your role:
"High School Mathematics Teacher"
"Adjunct Instructor, Business Analytics"
"Corporate Training Facilitator"
Avoid upgrading instructor to professor merely because both involve teaching adults. Academic ranks are institutional appointments, and inaccurate title translation can create credibility problems.
If your original title comes from another education system, use an official English translation when available. A brief parenthetical explanation may help:
"Lecturer (full-time university teaching appointment)"
Recognition versus production
If an American says my teacher, age and context help identify the level. If an adult says my professor, they probably mean higher education. My instructor emphasizes the person's teaching role but does not establish the institution.
When producing these words, choose the narrowest accurate label. If the appointment matters for hiring, verification, or a biography, confirm the official title rather than infer it.
Avoid status assumptions
The titles can carry prestige signals, but they do not measure teaching quality or professional value. A K–12 teacher, university professor, and technical instructor perform different work under different qualification systems.
Employment conditions also vary. Avoid assumptions about pay, tenure, job security, or degree level based only on professor or instructor. A neutral networking question is:
"What do you teach?"
rather than:
"Are you a real professor or just an instructor?"
For related group nouns, see faculty, staff, and student body meaning. For course terminology, see class versus course in American English.