Difference between Difficult and Tough

DIFFICULT vs TOUGH: NOUN

A violent or rowdy person; a hoodlum or thug.
A cruel and brutal fellow
Someone who learned to fight in the streets rather than being formally trained in the sport of boxing
An aggressive and violent young criminal
A rough; a bully; an incorrigibly vicious fellow; a bad character.
A person who is tough{7}; a ruffian; a thug.
A person who obtains things by force; a thug or bully.

Hard to control
Hard to manage, uncooperative, troublesome; eg. said of a person, a horse, etc.
Hard, not easy, requiring much effort
Hard to manage or to please; not easily wrought upon; austere; stubborn.
Hard to do or to make; beset with difficulty; attended with labor, trouble, or pains; not easy; arduous.
Not easy to persuade or convince; stubborn.
Not easy to please, satisfy, or manage.
Not easy to comprehend, solve, or explain.
Not easy to endure; full of hardship or trouble; trying.
Requiring considerable effort or skill; not easy to do or accomplish.
Not easy; requiring great physical or mental effort to accomplish or comprehend or endure
Requiring much effort and trouble

Very difficult; severely testing stamina or resolution
Unfortunate or hard to bear
Able to withstand great strain without tearing or breaking; strong and resilient.
Substantially made or constructed
Feeling physical discomfort or pain (`tough' is occasionally used colloquially for `bad')
Violent and lawless
Hard to cut or chew.
Physically hardy; rugged.
Aggressive; pugnacious.
Not given to gentleness or sentimentality
Physically toughened
Tough to cut or chew
Strong-minded; resolute.
Making great mental demands; hard to comprehend or solve or believe
Undergoing plastic deformation before breaking.
Difficult or demanding.
Rowdy or rough.
Harsh or severe.
Stubborn.
Rugged or physically hardy.
Difficult to cut or chew.
Strong and resilient; sturdy.
To make it a matter of difficulty; to make it a hard matter.
Prone to aggressive or violent behavior; rowdyish; -- of people, or groups.
Difficult to do, perform, or accomplish.
Severe; violent.
Not easily separated; viscous; clammy; tenacious.
Not easily broken; able to endure hardship; firm; strong; -- of objects and people.
Inclined to violent or disruptive behavior; rowdy or rough.
Difficult to endure; severe; harsh.
Trying or unpleasant.
Difficult to deal with; demanding or troubling.
Unfortunate; too bad.
Fine; great.
Stiff; rigid; not flexible; stubborn.
Having the quality of flexibility without brittleness; yielding to force without breaking; capable of resisting great strain.

Not easy
Synonyms Difficult, Hard, Arduous (see arduous), laborious, toilsome; obscure, knotty.
Hard to understand or solve; perplexing; puzzling: as, a difficult passage in an author; a difficult question or problem.
Hard to persuade or induce; stubborn in yielding; obstinate as to opinion: as, he was difficult to convince.
Hard to do, perform, or overcome; attended with labor, pains, or opposition; laborious: as, a difficult undertaking.
Not easy; requiring or dependent on effort; hard; troublesome; arduous.
To perplex; embarrass.
To make difficult; impede.
Hard to please or satisfy; not compliant; unaccommodating; rigid; austere: as, a person of difficult temper.

Hard to manage or accomplish; difficult; trying; requiring great or continued effort.
Not easily influenced; unyielding; stubborn; hardened; incorrigible.
Not easily separated; tenacious; stiff; ropy; viscous: as, a tough clay; tough phlegm.
Firm; strong; able to endure hardship, hard work, or ill usage; hardy; not easily broken or impaired.
Having the property of flexibility without brittleness; yielding to a bending force without breaking; also, hard to cut or sever, as with a cutting-instrument: as, tough meat.
Severe; violent: as, a tough rebuke or tirade; a tough storm.
Resistant to cutting or chewing
Very difficult
Making great mental demands
(idiom) (that's tough) Used to indicate recalcitrance or noncompliance with a complaint or demand.
(idiom) (tough it out) To get through despite hardship; endure.

Thorny, Trying, Unenviable, Delicate, Awkward, Rocky, Rough, Troublesome, Problematical, Arduous, Hard, Problematic, Challenging, Tough, Tricky

Unsentimental, Violent, Calloused, Sturdy, Pugnacious, Hardened, Rowdy, Bully, Rugged, Uncomfortable, Toughened, Toughie, Bad, Hard, Difficult

Thorny, Trying, Unenviable, Delicate, Awkward, Rocky, Rough, Troublesome, Problematical, Arduous, Hard, Problematic, Challenging, Tough, Tricky

Gristly, Unsentimental, Violent, Calloused, Sturdy, Pugnacious, Hardened, Rowdy, Bully, Rugged, Uncomfortable, Toughened, Bad, Hard, Difficult

It certainly can make for a difficult marriage.
Find it difficult to get around your bathroom?
Metaphors are more difficult to teach than similes.
Times have been so difficult in recent months.
The use of cryptography is complex and difficult.
Slow and difficult process to retrieve boarding pass.
Calamity player, pure summoner would be insanely difficult.
You are saying it is more difficult, music is more difficult?
Some dailies are more difficult than others, a lot more difficult.
Advancing racial equity is already difficult, but then you add the scope and it becomes more difficult.

Might be tough for a small order though.
This must be a tough time for you.
Diplomacy, especially under circumstances like these, is tough!
Recently I was going through a tough time.
WIld MUstangs and it must be tough fencing.
The girl was a tough one to find.
Probably tough to get a five star review and also tough to get a three star review.
Residue might be tough to get out, so you may have to hand scrub with a tough sponge.
It was tough, made you tough, cause you knew what to expect.
Going gets tough, the tough call the Iron Marines by purchasing this item you!