KDevelop is the KDE software development environment, i.e. it has an extensive editor for source code, tools for debugging, etc. In essence, it is the central tool within the KDE project for people who want to *develop*, not just use, software.
I'd be inclined to change the sentence I quoted, then, to "KDevelop is the KDE software development environment". I think that says what you intended, more clearly.
No, that's not what I meant. KDevelop is a program for software development that is part of KDE (the KDE desktop environment). For this kind of program, people typically use the term "integrated development environment (IDE)". In other words, KDevelop is an Integrated Development Environment (IDE) that is developed as part of the KDE desktop environment.
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