This forum uses a lot of acronyms, so I decided to make this list. I hope it will be useful.

Feedback and suggestions will be appreciated.

TECHNIQUES

NS - Naked Set

LS - Locked Set

HS - Hidden Set

LC - Locked Candidates

Note: Inside each Set there are more specific subgroups; Naked Pair (NP), Naked Triplet (NT), etc.

Those are the most basic techniques, you can read about them here.

ANS - Almost Naked Set

ALS - Almost Locked Set

AHS - Almost Hidden Set

ALC - Almost Locked Candidates

Note: ALS is a group of N cells which share N+1 candidates. If they share N+2 you could define it as Almost ALS or AALS, and you can have AAALS and so on. Same happens with AANS, AAHS... More info here.

CoALS - Combined Overlapping Almost Locked Sets Rule

DB - Death Blossom

QNS - Quantum Naked Set

PNS - Pseudo-Naked Set

MSLS - Multi Sector Locked Set

MSNS - Multi Sector Naked Set

MSHS - Multi Sector Hidden Set

SS - Skyscraper

DIC - Double Implication Chain

AIC - Alternating Interference Chain

DP - Deadly Pattern

DR - Deadly Rectangle

Note: You could also have ADP and ADR for Almost Deadly Pattern/Rectangle, the real deadly thing here is the terminology

RP - Remote Pair

ARP - Almost Remote Pair

RT - Remote Triplet

BARN - Bent Almost Restricted Naked Set

EM - Equivalence Marks

GEM - Graded Equivalence Marks

3DM - 3D Medusa

SDC - Sue-De-Coq

UR - Unique Rectangle

AUR - Almost Unique Rectangle

HUR - Hidden Unique Rectangle

EUR - Extended Unique Rectangle

Note: Unavoidable Rectangle and Almost Unavoidable Rectangle are NOT the same as Unique Rectangle and Almost Unique Rectangle, so it's better to not use the acronyms UR and AUR for them.

UL - Unique Loop

IQ - Incompatible Quads

BUG - Bivalue Universal Grave

MUG - Multivalued Universal Graves

HBUG - Hidden BUG

UCC - Uniqueness Clue Cover, yuck!

FC - Forcing Chain

DFC - Digit Forcing Chain

NFC - Nishio Forcing Chain

(D)CFC - (Dual) Cell Forcing Chain

UFC - Unit Forcing Chain

Note: There's also Triple Cell Forcing Chain, Quad Cell Forcing Chain, Region Forcing Chain and Contradiction Forcing Chain, but the acronym is not used.

APE - Aligned Pair Exclusion

ATE - Aligned Triplet Exclusion

CSP - Constraint Satisfaction Problem

DLX - Dancing Links, used to solve CSPs

JExocet - Junior Exocet

Note: You can read basic info about Exocets here. There's also a Senior Exocet but it's not abbreviated as SExocet, probably for the good of all.

Note: On Exocets some also talk about BC (Base Cells), TC (Target Cells) and CC (Cross Cells), but it's not common terminology.

DExocet - Double Exocet

GExocet - Generic (or Generalized) Exocet

Note: You can abbreviate even more using JE (JExocet), SE (Senior Exocet), DE (Double Exocet) and GE (Generic Exocet) but it's not preferred.

Note: Generic Exocets can also be Double and Junior so you can have DGE or JGE...

AGE - Almost Generic Exocet

GE2A - Generalized Exocet with Aligned Targets

SDP - Single Digit Patterns

POM - Pattern Overlay Method

BB - Bowman's Bingo

T&E - Trial and Error

TM - Triangular Matrix

FUD - First Upper Diagonal of a Triangular Matrix

BTM - Block Triangular Matrix

MBM - Mixed Block Matrix

PM - Pigeonhole Matrix

FM - Forbidding Matrix

SPM - Symmetric Pigeonhole Matrix

TDP - Technique of Tracks (Technique des Pistes, in French. More info in this PDF)

SIS - Strong Interference Set

WIS - Weak Interference Set

DLoop - Domino Loop

VLoop - Virus Loop

SK Loop - Steve Kurzhal's hidden-pair loop

SLG - Set Link Graphs

b/b plot - Bilocation/bivalue plot

(W)XYZ-Wing - Basic types of Wings

Note: More info in The Ultimate FISH Guide

More advanced types of Wings are defined here, here and here.

W-Wing - Basic type of Wing, named after George Woods, who discovered it.

M-Wing - Medusa Wing (simplest case of Medusa coloring)

L-Wing - Local Wing

H-Wing - Hybrid Wing

S-Wing - Split Wing

T-Wing - Transport Wing

Note: Check this post for a more extended & updated classification of Wings: March 13 2019

Note: Wings can also be classified based on the placement of V (value) and L (local) links: April 28 2019

More info here: What is XYZ-Wing Hybrid strategy?

BLR - Box Line Reduction

DS - Disjoint Subset

DDS - Disjointed Distributed Subset

ADDS - Almost Disjointed Distributed Subset

ER - Empty Rectangle

Note: ER are formed by lines (ERL) that cross in an intersection (ERI)

The ER can be spotted when an Empty mini-Area (EmA) is observed. More info in the hidden text of this post.

Note: You can read about TowER Cranes and LoadER Cranes here, of course it wouldn't be a good acronym list without some acronym-based puns...

RC - Restricted Common

RCD - Restricted Common Digit

RCC - Restricted Common Candidate [Outdated]

NL - Nice Loop

CNL - Continuous Nice Loop

DNL - Discontinuos Nice Loop

SSTS - Simple Sudoku Technique Set

AST - Advanced Solving Technique

Note:

- A pearl is a puzzle where initially the player cannot fill in any cell using SSTS (eliminations could be made, but no cells could be filled in directly)

- A diamond is a puzzle that doesn't have any "backdoor cells" (A backdoor cell is a cell where if you put in the correct value, with or without any logical reason, it would lead to the whole puzzle being solved by further moves under SSTS)

SOLVE NOTATION

Note: The Eureka notation often abbreviates even more the names of many basic techniques, but I won't include them here.

stte - Singles to the end, sometimes called Singles to end (ste)

btte - Basics to the end

lste - Locked Sets (and singles) to end

lclste - Locked Candidates, Locked Sets (and singles) to end

sstste - Simple Sudoku Technique Set (SSTS) to end

VARIANTS

LS - Latin Square

X - Diagonal Sudoku

NC - Non-Consecutive

AK - Anti-King, also known as Ferz

FNC - Ferz Non-Consecutive

AN - Anti-kNight

DP - Diagonal Pairs

FP - Forbidden Pairs

DG - Disjoint Groups (SudokuP)

AC - (Non-Consecutive) Adjacent Cells

CP - Contiguous Psets

SF - Frame Sudoku

GT - Greater Than Sudoku

KCC - Killer Cage Convention

MM - Multiple Modes

OTHERS

P&P - Pencil and paper

PM - Pencil-mark

RPC - Arcilla's Rows-per-Column list

CPR - Arcilla's Columns-per-Row list

EE - Arcilla's Eventual-Elimination

CEC - Candidate-Elimination Cell

DCB - Difference Cover-Base

DDS - Double Diagonal Symmetry of the clues

CP - Conjugate Pair

SE - Sudoku Explainer

SE - Main difficulty score given by the program Sudoku Explainer

ER - Explainer Rating

EP - (Explainer) Pearl rating

ED - (Explainer) Diamond rating

Note: You can read more about rating types in the first post of the Patterns Game

FOL - First Order Logic

MS-FOL - Multi-Sorted First Order Logic

LAS - Local Area Set

MSG - Minimum Set Group

UFG - The Ultimate Fish Guide thread

OTP - One Trick Pony, puzzle that requires only one hard trick

PE - Potential Elimination

SIN - Single Implication Network

NRC-, NRCT-, NRCZ-, and NRCZT- chains - Oriented 3D Chains

N-Rope, N-Braid, Z-Braid, and Z-Rope - Patterns used in Braid Analysis

MDCD - Multiple-digit Concept Diagrams

WU - Weekly Unsolvable Sudoku from Andrew Stuart's webpage

WSC - World Sudoku Championship

WPC - World Puzzle Championship

WTR - Wecoc Totally Rules (Ok, I just made that one up)