timeline

noun

time·​line ˈtīm-ˌlīn 

variants or time line

plural timelines or time lines

1

a

: an arrangement or occurrence (as of past events) in time : chronology

After interviewing the suspect, the wardens pieced together a timeline of events and gathered enough evidence to file appropriate charges …

—Texas Parks and Wildlife Department

b

: a visual representation of events associated with a particular period of time arranged chronologically along a line or in a linear format

The book also includes a timeline, showing which dinosaurs lived when and where, and how the Earth has changed over millions of years.

—The Children's Bookwatch

In her "Foundations of Western Civilization" course … Prof. Julia Gossard has her students create a timeline of the history of food …

—Thomas Keith

c

: a schedule of planned events, actions, etc. : timetable sense 2

With just under a year left until your nuptials, here's what's next on your wedding planning timeline.

—Sarah Hanlon

Giving the client a say in every step of the project could create a delay and throw off the timeline …

—Katie Bates

2

: a period of time especially with respect to some project or event : time frame

And what's the timeline for implementing these changes?

—Mark Sovel

The stakes are high, and the timeline is tight.

—Rio Longacre

… school districts can't open before Labor Day and must end by June 15. But to meet that compressed timeline … , districts have had to consider trade-offs.

—Donna St. George

3

: a stream of social media posts : feed sense 3e

Algorithmic timelines quietly replaced chronological ones, until our social-media feeds no longer took direction from us, but rather directed us where they wanted us to go.

—Yair Rosenberg

And if there's something funny … I make sure to Retweet so others can cleanse their timeline and enjoy.

—Andy Richardson

4

: a branch of a theoretical multiverse that exists in parallel with other branches

… the notion that we're surrounded by a multitude of parallel selves, one of which might be living in a better timeline than the one we're stuck in.

—S. I. Rosenbaum

—used especially in science fiction

… Dune: Awakening is set in an "alternate" timeline from the original Frank Herbert novels, where something has happened to change the course of history.

—Wes Fenlon

Examples of timeline in a Sentence

Recent Examples on the Web

There is no set timeline for the Supreme Court to respond to emergency docket requests, but recently, the justices have responded within two months of the initial petition being filed. —Jack Birle, The Washington Examiner, 14 Dec. 2025

Radiation exposure doesn’t follow the timelines of clean-up milestones. —New Atlas, 14 Dec. 2025

The Supreme Court has not announced a timeline for ruling on the broader tariff case, leaving uncertain whether companies like Costco will ultimately be able to recover millions of dollars in import duties, costs that retailers sometimes pass on to consumers. —Rey Covarrubias Jr, AZCentral.com, 13 Dec. 2025

General manager Bill Armstrong announced Cooley's timeline on Thursday. —CBS News, 13 Dec. 2025

Natura Resources is accelerating its timeline to deliver advanced nuclear energy, targeting the deployment of the first Generation IV reactor in the US by 2026 and the addition of gigawatts of power capacity between 2029 and 2032. —Aman Tripathi, Interesting Engineering, 12 Dec. 2025

Their work, published in the journal Lupus in January 2021 before Sanders’ death in July 2022, creates a comprehensive timeline for the decline in Austen’s health, which appears to have begun in the spring of 1816. —Ashley Strickland, CNN Money, 12 Dec. 2025

The Oracle spokesperson did not specify a timeline for turning on cloud computing infrastructure for OpenAI. —Jordan Novet, CNBC, 12 Dec. 2025

OpenAI's own reconstructed timeline raises bigger questions. —Kurt Knutsson, FOXNews.com, 12 Dec. 2025

Word History

First Known Use

1907, in the meaning defined at sense 1b