Factorio slang

1-4
Standard train configuration: one engine, 4 cars. Other common configurations are 1-4-1, 1-2 and 3-8
balancer
Setup of multiple splitters, distributing the items from input several belts between output belts. Often accompanied by the number of input and output belts.
blues
Microprocessors
bootstrap
Getting basic necessities working on nauvis or another planet. Usually includes setting up supply lines or a mall
buffer
A single or a row of chests with inserters for both input and output. Used in train stations or after ore smelters
casino
Space platform that washes asteroids into higher quality
compressed belt
Belt fully filled with no gaps between items
cryo...
Things from aquilo
cuba
Small island only occupied by biters. Usually kept alive to eat pollution while being unable to cause attacks
democracy
Biter genocide
di
Direct insertion. An inserter moving items from one building into another, without belt
early-game
Stage of a game before having construction robots
effing
Running over a belt while pressing the F key, picking up items
eff1, eff2, ....
Efficiency modules level 1, 2, ...
emp
Electromagnetic plant. The circuit assembler from Fulgora
greens
Basic circuits
LDS
Low density structures
LDS shuffle
Using a foundry making LDS and a recycler to get quality copper/steel from quality plastics. The foundry uses liquid copper and iron as input, who do not have quality and ara available in large quantities
legs
Exoskeletons
mall
Setup that produces parts to build the factory - belts, inserters, assembler
one-way
Train systems where trains never change direction and instead use loops
patch
Field of ore or cluster of wells.
prod
Productivity research level or productivity modules
pylon
The large power pole
reds
Advanced circuits
sa
Space Age, the DLC for Factorio
se
Space Exploration, a popular mod for the base game
spaghetti
Messy setups and belt knots
t1, t2, ...
Tier levels. t1 belts would be yellow, t2 belts red. Also used for different tiers of assemblers
taxi
Train dedicated to transporting a player. Usually to get back to fighting after respawning.
washing
Looping items through machines and recyclers with quality modules, increasing quality levels
zoo
Biter nests being walled off to neutralize it, done to capture it later with gleba tech