"Massager" vs "masseuse"

A friend of mine recently used the word masseuse to describe a person that gives massages. I have never heard of this terminology before so I'm wondering what the difference is between massager and masseuse?

To me, the -er ending makes it very obvious that it denotes "[a] person or thing that does an action indicated by the root verb; a person whose occupation is (the noun)." For instance:

• player: a person who plays
• driver: a person who drives
• songwriter: a person who writes songs

I realize sometimes there is a distinction between male and female actors (e.g. actor/actress). Other words that have different endings to indicate the person:

• assistant: a person who assists
• scientist: a person who practices science

Now with the last example, the -ist suffix denotes profession or religion, so in my case, massage therapist would also work. But what's with the word masseuse?

A masseuse is a female person who gives massages (the male is masseur). The origin of the term is French.

Massage therapist usually implies that the person has undergone some special training in the use of massage to alleviate medical conditions. They are typically licensed or certified in some manner:

How long does it take to become a Massage Therapist? In the U.S, legal minimum hours for obtaining a massage therapy license differ from state to state and range from 330 to 1,000 hours. [CareerExplorer]

A massager is a device that massages.

If you google massager you'll likely find a bunch of objects that vibrate or have knobs on them for being rubbed upon people's bodies.

The suffix -er just implies that it is a noun that performs a certain function. It does not imply that it is a person's profession. For example, an aircraft carrier.

The terms masseuse/masseur are titles used earlier when the industry was just beginning. The term today and the one that massage therapist prefer is (massage therapist) and not masseuse/masseur. When applying for licensing in the field, a school or licensing board will not and do not use these terms, masseuse/masseur. Most literature that refers to the field of massage therapy always uses the term massage therapist.

The term can also be viewed negatively by a massage therapist because they are terms used by an establishment that are seedy and questionable. An establishment that has build a reputation offering more than just a massage.