Agile Vocabulary: Sprint, Backlog, Velocity and 30 More Terms Explained
A plain-English guide to Agile and Scrum vocabulary — sprint, backlog, velocity, retrospective, epic, story points, and 30 more terms used in daily IT teamwork.
Agile is everywhere in software development — and so is its vocabulary. If you join a team that does Scrum or Kanban, you will hear these words from day one. Misunderstanding them leads to confusion in planning meetings, retrospectives, and daily standups. This guide explains the most important Agile and Scrum terms in plain English, with the context you need to use them correctly.
Core Scrum Terms
Sprint
A sprint is a fixed time period — usually 1 to 4 weeks — during which the team commits to completing a set of work items. At the end of each sprint, you should have a working, deliverable increment of the product.
“We’re in sprint 14. The sprint ends on Friday."
"This feature didn’t make it into the current sprint — let’s plan it for next sprint.”
Sprint Goal
The sprint goal is a brief statement that describes what the team is trying to achieve in this sprint. It gives focus and allows some flexibility in how the work is done.
Backlog
The backlog is the prioritised list of everything the team might work on. There are two kinds:
- Product backlog — the full list of features, improvements, and bug fixes for the product. Maintained by the Product Owner.
- Sprint backlog — the items the team commits to completing in the current sprint.
“That request is in the backlog but not prioritised yet."
"We need to groom the backlog before the next planning session.”
Backlog Grooming / Refinement
Grooming (also called refinement) is the process of reviewing, estimating, and clarifying backlog items before they are planned into a sprint. The team asks: is this item clear enough? Is it small enough? Do we understand what “done” looks like?
Story / User Story
A user story is a short description of a feature from the user’s perspective. The standard format:
“As a [type of user], I want to [do something], so that [benefit].”
Example: “As a registered user, I want to reset my password, so that I can regain access if I forget it.”
In practice, teams often drop the full format and just say “the password reset story.”
Epic
An epic is a large body of work that can be broken down into smaller user stories. An epic might represent a major feature, a complete user journey, or a technical initiative.
“Authentication is an epic with five stories: login, logout, password reset, MFA setup, and session management.”
Story Points
Story points are a unit of effort or complexity used to estimate user stories. They are relative, not absolute — a story with 8 points is roughly twice as much work as a story with 4 points, in the team’s estimation.
Common scales: Fibonacci sequence (1, 2, 3, 5, 8, 13, 21) or T-shirt sizes (S, M, L, XL).
“How many points do you estimate for this story?"
"We don’t estimate in hours — we use story points.”
Velocity
Velocity is the average number of story points a team completes per sprint. It is used for planning: if your team’s velocity is 30 points per sprint and the backlog has 150 points, you can roughly estimate 5 sprints.
“Our velocity dropped this sprint because of the production incident."
"Based on our velocity, we can finish the feature in 3 sprints.”
Sprint Planning
Sprint planning is a meeting at the start of each sprint where the team selects items from the backlog, estimates effort, and commits to a sprint goal.
Daily Standup / Daily Scrum
The daily standup is a short meeting (ideally 15 minutes or less) where each team member answers:
- What did I do yesterday?
- What will I do today?
- Is anything blocking me?
Sprint Review
The sprint review (sometimes called a demo) is a meeting at the end of the sprint where the team demonstrates completed work to stakeholders.
Sprint Retrospective
The retrospective (or retro) is a meeting at the end of the sprint where the team reflects on how they worked together:
- What went well?
- What could be improved?
- What will we change next sprint?
“Let’s raise that in the retro."
"In our last retrospective, we decided to improve our PR review process.”
Roles
Product Owner (PO)
The Product Owner represents the business and the users. They define and prioritise the product backlog and make decisions about what gets built.
Scrum Master
The Scrum Master facilitates the Scrum process — organising ceremonies, removing blockers, and helping the team follow Agile practices. They are not a project manager or a team lead.
Development Team / Engineering Team
The cross-functional team that does the actual work — developers, QA engineers, designers, etc.
More Agile / Kanban Terms
Kanban
Kanban is an Agile methodology that focuses on visualising work in progress and limiting the number of active tasks. Work is tracked on a Kanban board with columns like “To Do”, “In Progress”, and “Done.”
Work In Progress (WIP)
WIP is the number of tasks currently being worked on. Kanban limits WIP to prevent teams from taking on more than they can complete.
Definition of Done (DoD)
The Definition of Done is a checklist that defines when a task is truly complete — for example: code written, tests passing, code reviewed, documentation updated, deployed to staging.
Acceptance Criteria
Acceptance criteria are the specific conditions that a user story must meet to be accepted. They are written in plain language and testable.
“What are the acceptance criteria for this story?"
"The acceptance criteria say the export must complete in under 2 seconds.”
Spike
A spike is a time-boxed research task. When the team is uncertain about a technical approach, a spike gives a developer a fixed time (e.g., one day) to investigate and report back.
Technical Debt
Technical debt is the implied cost of quick-fix solutions that will require rework later. Like financial debt, it accumulates interest — shortcuts taken now slow down future development.
Blocker
A blocker is anything that prevents a team member from progressing on their task. Blockers are raised in standups.
“I have a blocker — I’m waiting on API credentials from the platform team.”
Increment
An increment is the sum of all completed product backlog items at the end of a sprint. The increment must be usable and potentially releasable.
Release
A release is when software is made available to end users. In Scrum, you can release at the end of every sprint or on a separate release cycle.
Stakeholder
A stakeholder is anyone who has an interest in the product — including users, customers, managers, and executives who are not on the development team.
Common Agile Phrases
| Phrase | Meaning |
|---|---|
| ”Let’s prioritise this” | Move it higher in the backlog |
| ”We can’t commit to this sprint” | Not enough capacity to include it |
| ”We need to break this down” | The story is too large — split it |
| ”What are the acceptance criteria?” | How do we know when it’s done? |
| ”Is this in scope?” | Is it part of what we agreed to build? |
| ”Let’s park that for now” | Set it aside; discuss later |
| ”We’re blocked on this” | Cannot proceed; need someone else’s input or action |
| ”This is a P0/P1” | P0 = critical (must fix now); P1 = high priority |