female bar owner; proprietress
Polite term for a woman who runs a bar, snack, or small drinking establishment. Often used by customers and staff.
See also: ママ
The proprietress of that bar is very friendly.
Affectionate or familiar term for a mother or a housewife, often used by children or in casual community contexts. Can also be used as a prefix (e.g., ママさんバレー).
female pet owner; pet mom
Used in pet communities to refer to a female pet owner, often with a nurturing connotation.
Our dog's mom never misses a daily walk.
The proprietress of that bar is very easy to talk to.
Mama-san, the usual, please.
Mom, what's today's snack?
I went to lunch with the neighborhood moms.
My dog's mom (owner) is a very kind person.
飼い主 is the neutral, gender-unspecified word for 'pet owner', while ママさん highlights a nurturing female owner in pet-community speech.
counter for people
From ママ (mama) + honorific さん. ママ is a loanword from English 'mama', used in Japanese for 'mother' or a female bar owner.