The phrase "primary application" refers to the main or most important purpose or use of something. It is the main reason why something is used or exists. Full definition
In fact, it's the inability to create this condition using popular «green» technologies that is one of the main reasons we think ductless mini splits are not an appropriate primary application for our climate. (energyvanguard.com)
Wind Energy's primary application of relevance to climate change mitigation is to produce electricity from large wind turbines located on land or offshore. (climateandcapitalism.com)
Proficient in the Lua scripting language, with primary application in adventure game scene scripting and mini-game development. (ifest.us)