a character printer that automatically prints stock quotations on ticker tape
"The old newsroom featured a flickering ticker that continuously printed the latest stock prices onto a long strip of paper."
One who makes a tick mark.
"The accountant hired a ticker to quickly count and verify every transaction on the ledger."
In plain English: A ticker is a device that displays stock prices and other financial news as they happen, usually moving across a screen line by line.
"The stock ticker flashed red numbers across the trading floor, warning investors of another market drop."
The word ticker combines the verb to tick with the agent suffix -er, originally referring to a device that makes ticking sounds or movements. It was first used in English to describe mechanical stock market recorders before expanding to mean any rhythmic sound-maker or pulse monitor.