Definely is an AI platform embedded directly in Microsoft Word, built for lawyers who need to draft, review, proofread, and understand complex contracts without leaving their existing workflow. Its "Vault" feature searches precedent and clause libraries, "Cascade" tracks the ripple effects of a change across a document, and "Proof" and "Enhance" handle proofreading and AI-assisted analysis.

The company was founded in 2020 in London by former Freshfields lawyers, and reports over 150 law firm and in-house customers. It raised a $30M Series B in June 2025 (led by Revaia, with Clio participating as an investor), following a $7M Series A, bringing total funding to roughly $40M.

Definely reports SOC 2, ISO 27001, ISO 42001, and GDPR compliance, but does not publish a statement on whether customer data is used to train models, and does not name its underlying AI model provider. Pricing is enterprise/quote-based and not publicly listed.