What does "overqualified" actually mean to an employer?

It usually means the employer thinks your experience, qualifications or past level go well beyond what the job needs, and they are worried about what that could lead to. The word is rarely about your ability; it is about risk.

Common worries behind it:

• You will get bored and leave when a better job appears.
• You will expect more pay or a bigger title than the role offers.
• You may find it hard to take direction from a less experienced manager.
• You may want to do the job your own way.

Your resume and cover letter can address these worries without hiding anything:

• Tailor the resume so the most relevant skills lead.
• Explain your genuine reason for wanting this role.
• Show you are happy to do hands-on work.

Some employers welcome extra experience; others prefer a closer match. A clear, honest reason for applying is the most useful thing you can give them.