Actually, if you're looking for American terms for "wanking" as opposed to wanker, the list is much longer.............

Answer the Bone-A-Phone
Assault on a Friendly Weapon
Backstroke Roulette
Baiting your Hook
Batting Practice
Bash The Candle
Beat Off
Beating the Bait
Beating the Bishop
Beating the Dummy
Beating the Snake
Beating the Stick (Please no more "beat")
Beating your Meat
Being your Own Best Friend
Bleed the Weed
Blow Your Load
Bludgeon the Beefsteak
Boppin' your Bologna
Buckin' it
Buffing the Banana
Buffing the Wood
Burping the Worm
Butter Your Corn
Calling Down For More Mayo
Calling All Cum
Carrying Weight
Cast Off
Changing your Oil
Charm the Cobra
Choaking Charlie 'till He Throws Up
Choke Kojak
Choke your Chicken
Civil War
Cleaning out your Rope
Clean the Pipes
Clean your Rifle
Clubbing Eddy
Couch Hockey for One
Cracking the Fat
Crank the Shank
Cranking
Cranking For Cum
Crank Your Cordiano (for Joe - the man with forearms like Popeye)
Crown the King
Cuff the Carrot
Cuffing the Puppy
Cum The Scum
Custer's Last Stand
Date Miss Michigan
Date Mother Palm and Her Five Daughters
Devil's Handshake (Catholic School)
Diddle
Dishonorable Discharge
Disseminating
Doddle Whacking
Doodle Your Noodle
Do The Dew
Drain the Dragon
Drain the Monster
Drain the Vein
Dropping A Line
Dropping Stomach Pancakes
Firm Your Worm
Fist Fuck
Fist your Mister
Five Against One
Five Finger Knuckle Shuffle
Five Knuckle Olympics
Flogging Your Dong
Flogging Your Log
Flute Solo
Flying a Kite
Fondle the Fig
Freeing the Willies
Frigging the Love Muscle (British)
Gallop the Antelope
Gallop the Maggot
Getting In Touch With Your Manhood
Getting In Touch With Yourself
Getting to Know Yourself Personally in the "Biblical Sense"
Getting Your Caps Peeled
Giving it a Tug
Giving the John Hancock
Grease the Pipe
Greasing your Bone
Hack the Hog
Ham Shank
Hand Job
Hands on Training
Hand to Gland Combat
Hand Work
Having a Roy (Australian)
Have it Off
Have One Off the Wrist
Hitchhike Under the Big Top
Hitching to Heaven
Hit the Ham
Holding All The Cards
Holding Your Sausage Hostage
Hone your Bone
Hump your Fist
Hump your Hose
Humpin' Air
Ironing Some Wrinkles
Jack Hammer
Jack Off
Jackin'
Jackin' the Beanstalk
Jag Off
J Arthur Rank (British rhyming slang - wank)
Jazz Yourself
Jelly Roll
Jerk Off
Jerk the Gherkin
Jerk the Johnson
Jiggle the Jewelry
Jimmying your Joey
Killing the Beast
Knock the Top Off
Knuckle Shuffle on your Piss Pump
Launching the Hand Shuttle
Leakin' the Main Drain
Loping your Mule
Making the Bald Guy Puke
Making Nut Butter
Making Yogurt
Mangle the Midget
Manipulate the Mango
Manual Override
Masonic Secret Self Handshake
Massage your Muscle
Massage your Purple-Headed Warrior
Measuring For Condoms
Milking the Bull
Milking the Lizard
Milking the Monkey
Milkywaying
Moulding Hot Plastic
Nerk your Throbber
Oil the Glove
Oiling The Pogo Stick
One Handed Clapping
One Man Show
One Man Tug-O-War
Pack your Palm
Paddle the Pickle
Paint the Pickle
Pain the Walls
Pam Anderson Polka
Pat the Robertson
Peel Some Chilis
Peel the Banana
Peel the Carrot
Petting Your Dog
Playing With Dick
Playing With Susi Palmer and her five friends
Playing With Your Noodle
Play Pocket Pool
Play the Organ
Play the Pisser
Play the Piss Pipe
Play the Skin Flute
Play the Stand-Up Organ
Playing With the Snake
Playing Your Instrument
Play With Yourself
Pocket Pinball
Pocket Pool
Polish the Chrome Dome
Polish the Rocket
Polish the Sword
Polish your Bayonet
Polish your Helmet
Polish your Knob
Popping the Porpoise
Popping The Purple Pimple
Pound Off
Pound Your Flounder
Pound Your Piss Pump
Pounding your Pud
Pudwhacking
Pud Wrestling
Puddin'
Pull the Root
Pulling The Wire
Pulling Your Goalie
Pull Off
Pulling The Piss Pump
Pull the Pole
Pull the Pope
Pull Your Pud
Pull your Taffy
Pumping For Pleasure
Pumping For Power
Pump the Python
Punchin' The Clown
Punchin' The Munchkin
Punishing Percy
Punishing the Bishop
Ram the Ham
Ride the Great White Knuckler
Rolling The Fleshy Blunt
Roman Helmet Rhumba
Ropin' the Long Horn
Rope the Pony
Roughing up the Suspect
Rounding Up the Tadpoles
Routin' for the Yankees
Rub One Out
Rub the Unicorn's Horn
Runka (Swedish)
Scraping Your Carrot
Scratching the Itch
Seasonin' Your Meat
See Mrs. Palmer & Five Daughters
Self Love
Sending out the Troops
Shaking Hands With Abe Lincoln
Shaking Hands With the Governor
Shaking Hands With Shorty
Shaking Hands With the Unemployed
Shake the Snake
Shifting Gears
Shine Your Pole
Shining The Helmet
Shooting Enemies
Shooting Putty at the Moon
Shooting Sherman
Shucking Bubba
Slam the Hammer
Slammin' the Salami
Slappin' Pappy
Slapping the Clown
Slap Boxing the One-Eyed Champ
Slap My Happy Sacks
Slap the Salami
Slapping the Cyclops
Slapping your Chub
Slinging Jelly
Sloppy Joe's Last Stand
Sloppy Sign Language
Stroke the Stallion
Smacking your Sister
Snap the Monkey
Snap the Whip
Snapping Your Carrot
Spank the Frank
Spank your Monkey
Spear Chucking
Spreading the Mayo
Spunk the Monk
Squeeze the Cream From the Flesh Twinkie
Squeeze the Lemon
Squeezing the Tube of Tooth Paste
Squeezing the Burrito
Staff Meeting
Stall Clapping
Stir the Soup
Stroke Off
Stroking It
Stroking your Goat
Stroke your Poker
Taking a Shake Break
Tame the Wild Hog
Tamp your Tool
Tap the Turkey
Tease the Python
Tease the Weasle
Tenderize the Meat
The Erky Jerk
The Sticky Page Rhumba
Threading a Needle
Throw off a Batch
Throwin' Down
Thump the Pump
Tickle the Elmo
Tickle the Pickle
Toss Off
Toss the Boss
Toss the Turkey
Tugging your Toobsteak/Toobsnake
Tug of War with Cyclops
Tuning the Antenna
Tussle with Your Muscle
Unwapping the Pepperoni
Varnishing the Cane
Wailing
Walk the Dog
Walking Willie the One Eyed Wonder Worm
Wank (British)
Waxing the Dolphin
Wax your Jackson
Wax your Weasel
Wax your Willy
Whack Off
Whack Your Tack
Whip the Bishop
Whip the Dummy
Whip your Dripper
Whipping the One-Eyed Wonder
Whipping the Pony
Whipping the Window Washer
White Water Wristing
Whizzin' Jizzim
Wiggling your Worm
Winding the Jack In The Box
Wonk your Conker
Working a Cramp out of your Muscle
Working your Willy
Wrestling the Eel
Wring Out your Rope
Wring Your Thing
Yahtzee
Yank My Doodle (It's a Dandy)
Yank Off
Yank your Crank

And if you're female.....................

3 Point Shot
A Night in With the Girls
Airing the Orchid
Auditioning the Finger Puppets
Beat the Beaver
Beating Around the Bush
Brushing The Beaver
Carpet Bumping
Cat Got Tongue
Checking for Squirrels
Clam Bake for One
Cleaning your Fingers
Clitters
Coming Into Your Own
Countering Cunts
Creamin'
Coming Into Your Own
Cunt Cuddling
Dialing the Rotary Phone
Digging a Trench
Doing your Nails
Dousing the Digits
Drilling For Oil
Engaging in Safe Sex
Erasing the Problem
Fanning the Fur
Feeding the Bearded Clam
Feeding your Slot
Fiddling the Bean
Fingerbating
Fingerpainting
Finger Blasting
Flickin' the Bean
Flit your Clit
Fucking Without Complications
Gagging the Clam
Gagging the Lips of Love
Genital Stimulation via Phalangetic Motion
Get a Lube Job
Get To Know Yourself
Get a Stinky Pinky
Going Mining
Groping the Grotto
Greasing your Hips
Grissle Rub
Gusset Typing
Having Sex With Someone you Love
Hee-Haw with wrinkled Mee-Maw
Hitchhiking South
Hitchhiking to Heaven
Hitchhiking Under the Big Top Jillin' Off
Jocelyn Eldering
Let Your Fingers do the Walkin'
Levy Break Limbo
Making Soup
Manual Override
Muffin Buffin'
Nulling the Void
Paddling the Pink Canoe
Pampering the Pussy
Parting the Red Sea
Pearl Fishing
Pet the Petunia
Pet the Pussy Cat
Polishing the Nugget
Polishing the Peanut
Polishing the Pearl
Play Poker
Play the Clitar
Play Couch Hockey for One
Play the Silent Trumbone
Playing With Her Pineapple
Playing with Mrs. Palmer's Five Daughters
Playing With the Man in the Boat
Pushing the Button
Pussy Soccer
Riding the Unicycle
Rolling the Dough
Rubbin' the Nubbin
Rubbing the Donut
Rubbing the Red Pussycat
Scoring the Hoop
Slapping the Mackerel
Soaking the Whisker Biscuit
Spelunking
Spearing the Bearded Clam
Squeeze the Peach
Strumming
Strumming the Banjo
Surfing the Channel
Teasing the Kitty
Teasing the Tuna Taco
Testing the Plumbing
The Virgin's Release
Tickling the Taco
Tiptoe Through the TwoLips
Toggling the Bit
Tossing Pink Salad
Trolling the Bermuda Triangle
Two Finger Taco Tango
Washing your Fingers


Spaw