Module

Modular programming is a software design technique that emphasizes separating the functionality of a program into independent, interchangeable modules, such that each contains everything necessary to execute only one aspect of the desired functionality.

Source: https://en.wikipedia.org/wiki/Modular_programming

(Software) Package

A collection of functions written in a single language bundled with additional content like documentation, unit test, sample data etc.

Source: https://en.wikipedia.org/wiki/Package_development_process

Component

An individual software component is a software package, a web service, a web resource, or a module that encapsulates a set of related functions (or data).

Source: https://en.wikipedia.org/wiki/Component-based_software_engineering#Software_component

Sources

Technical source code, structures and definitions of an IT solution

(JLN) Business Process

Functional Unit

An interchangeable unit that provides a piece of business functionality

(Software) Repository

A storage location for software packages & other technical sources

Source: https://en.wikipedia.org/wiki/Software_repository