For a lot of new users, trying to read a route or understand a speedrunner can be quite confusing. Ocarina of Time is a large game, and with it comes many, many terms and shorthands. Hopefully, this resource will help you make sense of this complex speedrun-speak.
Locations:
Abbreviation
Description
BotW
Bottom of the Well
DC
Dodongo's Cavern (or more rarely, Desert Colossus)
DM
Death Mountain (usually Death Mountain Trail)
DMC
Death Moutain Crater
DMT
Death Mountain Trail
Deku
Deku Tree
Fire
Fire Temple
Forest
Forest Temple OR Kokiri Forest/Lost Woods area (depending on context)
GC
Goron City / Ganon's Castle (depending on context)
GF / Fortress
Gerudo Fortress
GTG
Gerudo Training Grounds
GV
Gerudo Valley
HF/Field
Hyrule Field
Wasteland
Haunted Wasteland
IC
Ice Cavern
Jabu
Jabu Jabu's Belly
Kak
Kakariko Village
Kokiri/KF
Kokiri Forest
LH
Lake Hylia
LLR
Lon Lon Ranch
LW
Lost Woods
SFM
Sacred Forest Meadow
Shadow
Shadow Temple
Spirit
Spirit Temple
ToT
Temple of Time
Water
Water Temple
ZD
Zora's Domain
ZF
Zora's Fountain
ZR
Zora's River
Items:
Abbreviation
Description
BGS
Biggoron Sword / Broken Goron's Sword
BK
Boss Key
Chus
Bombchus
DF
Din's Fire
Explosives
Bombs or Bombchus
FA
Fire Arrows
FW
Farore's Wind
Gaunts
Silver and/or Gold Gauntlets, depending on context
HC
Heart Container
HP
Heart Piece
HS / Hook
Hookshot
Hovers
Hover Boots
IA
Ice Arrows
IBs
Iron Boots
LA
Light Arrows
Lens
Lens of Truth
MS
Master Sword
MoT
Mask of Truth
NL
Nayru's Love
Nuts
Deku Nuts
OoT
Ocarina of Time (or the game itself)
Potion
Odd Potion (in some contexts, red/blue/green potion)