Meanings of small tot in English

They say Queen Victoria drank a small tot each night before retiring.

He did not answer, but leaned forward and poured himself another small tot of whisky.

Julia sipped her small tot of whiskey, making it last, but the women cops slugged theirs like heroes.

In his little pantry Morgan waited until the screen door had closed, then poured himself a small tot of rum and sipped appreciatively.

Fathers who aged twenty years in a single season would leave their small tots behind, orphaning them.

Willie and his brother Frank began playing pool as very small tots playing an adult kind of pool, driving the ball with finesse and accuracy.

I feels so hurted I was left in 1940 with 4 small tots & a baby to Be borne 3 months later.