In Buddhism, the English words 'suffering' & 'unsatisfactoriness' are often used as translations of the Pali word 'dukkha'. What is the difference between 'suffering' & 'unsatisfactoriness'?
'Unsatisfactoriness' is one of the Three Characteristics. 'Unsatisfactoriness' refers to an inherent quality of all (conditioned) material & mental things.
The cause of unsatisfactoriness is impermanence. Due to impermanence, all (conditioned) mental & material cannot be relied upon for lasting true happiness. Therefore, all impermanent things have a quality of unsatisfactoriness, be it major or minor.
A Buddha or fully enlightened person cannot eradicate unsatisfactoriness because every conditioned phenomena in the universe, including stars & planets & the body & mind of a Buddha, contains the characteristic of unsatisfactoriness. A Buddha experiences unsatisfactorines in everything they see, hear, smell, taste, touch & cognize (except Nirvana. Nirvana is satisfactory because it is the unconditioned peace experienced from letting go of craving).
Then, friend Yamaka, how would you answer if you are thus asked: A monk, a worthy one, with no more mental effluents: what is he on the break-up of the body, after death? Thus asked, I would answer, ‘Form is impermanent… Feeling… Perception… Fabrications… Consciousness is impermanent. That which is impermanent is unsatisfactory. That which is unsatisfactory has ceased and gone to its end. Very good, my friend Yamaka. Very good. SN 22.85
Now I am frail, Ananda, old, aged, far gone in years. This is my eightieth year, and my life is spent. Even as an old cart, Ananda, is held together with much difficulty, so the body of the Tathagata is kept going only with supports. It is, Ananda, only when the Tathagata, disregarding external objects, with the cessation of certain feelings, attains to and abides in the signless concentration of mind, that his body is more comfortable. DN 16
Experiencing unsatisfactoriness is the cause of eradicating craving & suffering. When conditioned things are seen with wisdom as unsatisfactory, those conditioned things cease to be desirable. Thus, when desire (craving) ends, suffering ends.
Seeing (impermanence, unsatisfactoriness & not-self) thus, the well-instructed disciple of the noble ones grows disenchanted with form, disenchanted with feeling, disenchanted with perception, disenchanted with fabrications, disenchanted with consciousness. Disenchanted, he becomes dispassionate. Through dispassion, he is fully released. With full release, there is the knowledge, 'Fully released.' He discerns that 'Birth is ended, the holy life fulfilled, the task done. There is nothing further for this world.' SN 22.59
Therefore, unsatisfactoriness & suffering are not the same thing because experiencing unsatisfactoriness results in not experiencing suffering.
"All conditioned things are unsatisfactory" — when one sees this with wisdom, one turns away from suffering. This is the path to purification. Dhammapada 278
Below are pictures of unsatisfactoriness; i.e, undesirable things that cannot bring true lasting permanent happiness.
Dukkha is a vast subject. After 50 years of practicing Buddhist mindfulness meditation based upon the Satipatthana Sutta as taught by the late Venerable Namgyal Rinpoche, I am able to talk about the kind of Dukkha that mindfulness meditation deals with, along with a little common-sense. For example, mindfulness helps a person stay objective. Hence, physical pain remains simply that--physical pain without an emotional response such as self-pity or anger. Yet, it remains painful to observe a loved one suffer, for that is the nature of compassion. Advanced states of mindfulness meditation have three other general benefits: (1) It allows a person to explore the siddhis (psychic powers that depend upon previous karma), such as perceiving the nature of karma and the nature of the Bodhicitta. (2) It frees the mind to function more in accord with the awareness, wisdom, and love of the Bodhicitta. (3) It brings a person to Enlightenment and helps them to understand Enlightenment, just as the Buddha promised. Beyond that, I am inclined to agree with the Tibetan Buddhists that the true purpose of Enlightenment is to help others suffer less rather than to achieve lasting true happiness. If you want more than that, then the karma-vipaka of that wish will turn around and bite you with disappointment.
'Suffering' is the subject of the Four Noble Truths. 'Suffering' refers to psychological or emotional trauma, including sorrow, lamentation, pain, grief & despair.
For example, when a woman is to give birth to a child, this event is often one of great anxiety, worry & physical pain, which is why the Four Noble Truths explain there is suffering associated with 'birth' (jatipidukkha).
Then for nine or ten months the mother shelters the embryo in her womb with great anxiety, as a heavy burden. Then, at the end of nine or ten months, she gives birth with great anxiety, as a heavy burden. MN 38
Similarly, aging, illness, death, separation from the loved, etc, are experiences of human suffering when human beings are tied up in these experiences with self-view (attachment).
Now at that time a certain householder's dear & beloved little son, his only child, had died. Because of his death, the father had no desire to work or to eat. He kept going to the cemetery and crying out, "Where have you gone, my only little child? Where have you gone, my only little child?" The Blessed One said: "That's the way it is, householder. That's the way it is — for sorrow, lamentation, pain, distress, & despair are born from one who is dear, come springing from one who is dear. MN 87
Nakulapita went to the Blessed One and said "Lord, I am a feeble old man, aged, advanced in years, having come to the last stage of life. I am afflicted in body & ailing with every moment." The Blesssed One said: "'Even though I may be afflicted in body, my mind will be unafflicted.' That is how you should train yourself." Now, how is one afflicted in body & afflicted in mind? He assumes form (the body) to be the self, or the self as possessing form, or form as in the self, or the self as in form. He is seized with the idea that 'I am form' or 'Form is mine.' As he is seized with these ideas, his form changes & alters, and he falls into sorrow, lamentation, pain, distress, & despair over its change & alteration. SN 22.1
The causes of suffering, as explained in the 2nd Noble Truth & Dependent Origination, are ignorance, craving, becoming, attachment & self-identifying (self-view).
A Buddha or fully enlightened person has eradicated all suffering. A Buddha experiences no suffering in life whatsoever.
Below are pictures of suffering.
There is no difference as they are both inexact translations of "Dukkha" in English.
I think the best definition of dukkha is "believing "what is" should be some other way".
So, if one smashes their finger with a hammer the result would be a sensation that is not good or bad in the ultimate sense.
When one reacts by crying and trying to distract oneself from the pain sensation then that is dukkha, that is believing very deep down that reality is no good as it is.