ママさん

Meanings

female bar owner; proprietress

Polite term for a woman who runs a bar, snack, or small drinking establishment. Often used by customers and staff.

〈場ば所しょ〉のママさんthe proprietress of a bar/snack
あのバーのママさんはとても話はなしやすい。
The proprietress of that bar is very easy to talk to.
〈動どう物ぶつ〉のママさんthe female owner of a pet
うちの犬いぬのママさんはとても優やさしい人ひとです。
My dog's mom (owner) is a very kind person.

ママN3
ママ is the plain, informal word for a bar hostess or 'mommy', while ママさん adds さん to sound more polite or affectionate.
おかみさん sense 1
おかみさん is a traditional term for the proprietress of a shop, inn, or restaurant, while ママさん specifically refers to the owner of a bar or snack club.
お母かあさんN5sense 2
お母さん is the standard polite word for 'mother', while ママさん is a more casual, affectionate variant often used by children or in community contexts like ママさんバレー.
飼かい主ぬしN2sense 3
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.

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.