In project management, float or slack is the amount of time that a task in a project network can be delayed without causing a delay to:

An activity that has a total float equal to zero is said to be a 'critical activity', which means that a delay in the finish time of this activity will cause the entire project to be delayed

"A spike solution is a prototype, working code that explores a possibility or solves key functionality of a specific project requirement, thus reducing the overall risk associated with the project."

Stovepipes are “systems procured and developed to solve a specific problem, characterized by a limited focus and functionality, and containing data that cannot be easily shared with other systems.” (definition by DOE 1999). Stovepipe system is a legacy system that is an assemblage of inter-related elements that are so tightly bound together that the individual elements cannot be differentiated, upgraded or refactored.

Ubiquitous language is a common language used by both the Domain experts/Business analysts and the Developers to easily communicate across the whole team while avoiding any miscommunication. Ubiquitous language is the heart of Domain Driven Design (DDD). It is a simple domain specific language and highly readable, used in all forms of communications including the code, diagrams, design documents, etc. Ubiquitous language should be able to explain all concepts of that domain, and can explain new terms using already understood terms.