UNSC Colloquial Slang

"Being a listing of the colloquial terms utilized by the most glorious and reverend soldiers of the United Nations Space Command and its many holy branches, so that the Faithful may know and use the words of the righteous in their own Crusades against the xenos and the soulless. Praise be the UNSC. Praise be Earth."
-From the New Pacifican Military Dictionary, 2557 Edition
Soldiers, as they always have, give nicknames to things. The UNSC is no different. A few of the nicknames for their equipment and those used by their various foes (as of 2558) are as follows;
(Note; For pre-2558 standard equipment see ChatterNet Record; "Halo Encyclopedia")
ARC-920 "Railgun": Rail Rifle, "Two Sticks And A Rock", Holepuncher, Lightning Gun, Bass Cannon, Shock Rifle, Can Opener, Hand-Held Frigate
M57 Pilum: Toob, Thump Tube, Flinger (from the rocket magazine ejection action), Flyswatter, Thunderstick, Lawn Chair, Problem Solver
M395 Designated Marksman Rifle: Melon Popper, Candace, Short Sniper, Ranger Rifle, Mike Romeo, Armsreach, Trooper's Mistress (from the UNSC Army's love of the weapon), Long Rifle. 
MLRS-1 Hydra: Tampon Gun, Bolter, One Man Salvo, Katushya, Chaser, Seeker Six, Seeker, Hound Launcher, Gyroc, Huggle (derrivative of HGL, Hydra Gyroc Launcher), Monster
M739 SAW: Saw, Ripper, 249, Mower, Mulcher, "We Regret To Inform You", MG, Drum Gun (from 72 round circular drums), Chainsaw, Shredder, Door Holder, Line Holder, Suppressor, Answer (specifically M739s armed with air burst smart munitions but applied to entire weapon line)
M363 "Sticky Detonator": Sticker, Sticky, Magbomb, Can Launcher, Timebomb, Surprise, Tick Tick Boom
M319 Individual Grenade Launcher: Nade Launcher, November Lima, Tube, Thumper, Grenade Flinger, Bomb Thrower, Can Shooter
Enemy Weapons: Covenant
Type-55 Storm Rifle: Whale Gun, Plasma Hose, Spitballer, Paintball Gun, Ugly Mother****er, Melt Rifle, Melter, Spewer, Blue Gun
Type-31 Needle Rifle: Needler Rifle, Eyetaker, Blam Gun, Needle Gun, Pig Sticker (local origin; extensive use of captured Type-31s by milita units against Unggoy combat squads during Battle of Pacifica), Pink Death, Needler Carbine, Stitch Up, 1-2-3 BOOM
Type-27 Beam Rifle: Whale ****, Fish Sniper, Leg, Xeno Leg, Whale Leg, Log, Long Gun
Type-53 Plasma Caster: Spam Cannon, Spam Gun, Blueberry Launcher, Blueberry Gun, Skipper, Plasma Bow (secondary fire), Sticky Launcher, PC, Hall-Clearer, Armory Broom, Sticky Spammer
Type-50 Concussion Rifle: Hand mortar, Crusher, Bonesmasher, Sound Gun, Rattler, Knockback, Truckstopper
Enemy Weapons: Forerunner
Z-250 Lightrifle: Flashlight, Line-gun, Strobe, Longshot, Raygun, Hardlight Gun
Z-110 Boltshot: Pocket Shotty (Requiem variant), Nailgun (Requiem variant), Peashooter, Lightpistol, Cube, Boltgun
Z-130 Suppressor: Grass shooter, Hail, Lightshow, Disco Gun, Hit N Miss, Spray, Sewing Machine (Created Variant, based on firing noise)
Z-180 Scattershot: Light shotty, space shotty, Music Box (Requiem variation, based on weapons reloading noise), Block Shot, X Gun, Bouncer, Eraser (from hardlight particles effect on biological matter)
Z-750 Binary Rifle: Long Line, Problem Solver, Ashmaker, Oneshot (Requiem Variant), Person Remover, Space Sniper, Robosniper, Dog Gun (from Crawler Sniper variants)
Z-390 Incineration Cannon: Obliteration Cannon, Obliterator, Sun Gun, Sunlauncher, Fireball, Volcano Gun, **** You, Hellfire, Exterminator