As a feeling, being straight fire is when you're on the up and up, dropping low with your homies, making that dough, spitting that game, you know, ordinary hood shit.

When referring to an object, place, or event, straight fire means that its top notch, better than the rest, just mad niggerish in general, right up my alley.

From STEM, an abbreviation short for "Science, Technology, Engineering and Mathematics", a STEMlord is a pejorative term for a particular kind of person who has studied in these areas at university or works in these fields who holds a pretentious, condescending attitude to anyone who has studied in any other fields, particularly the Arts and Humanities. They typically believe themselves to be more "intelligent" and "rational", while generally remaining incredibly ignorant outside of their areas of expertise and having the charisma of a rotting pig's backside.

adj. Anything that is so good that makes you trip over yourself so bad that you think you are on something.
(Awesome, Cool, etc.)
Usually a lot of emphasis on Fire

Straight fire is a common Aussie slang. It's used to describe something/someone so unperceivably hot, that just saying hot doesn't do justice. In order for someone/something to be straight fire, the majority of your squad must agree with it. Fire emoji is a good synonym of straight fire.

The strongest kinda bud you can get your hands on

makes your lungs burn