Real Dictionary

mother
countable noun: Your mother is the woman who gave birth to you. You can also call someone your mother if she brings you up as if she was this woman. You can call your mother 'Mother'.
verb: If a woman mothers a child, she looks after it and brings it up, usually because she is its mother.

mother in American English 1
a woman who has borne a child; esp., a woman as she is related to her child or children
noun: a female parent

mother in American English 2
mother of vinegar
noun: a stringy, mucilaginous substance consisting of various bacteria, esp Mycoderma aceti, that forms on the surface of a fermenting liquid and causes fermentation when added to other liquids, as in changing wine or cider to vinegar

mother in American English 3
noun

mother in British English 1
noun: a female who has given birth to offspring

mother in British English 2
noun: a stringy slime containing various bacteria that forms on the surface of liquids undergoing acetous fermentation. It can be added to wine, cider, etc to promote vinegar formation