Dukkha

Translations of dukkha
English	suffering, pain, unsatisfactoriness, etc.
Pali	dukkha (Dev: दुक्ख)
Sanskrit	duḥkha (Dev: दुःख)
Bengali	দুঃখ dukkhô
Burmese	ဒုက္ခ (IPA: [doʊʔkʰa̰])
Chinese	苦 (Pinyin: kǔ)
Japanese	苦 (rōmaji: ku)
Korean	苦 (ko)
Sinhala
Tibetan	སྡུག་བསྔལ། (Wylie: sdug bsngal; THL: dukngal)
Thai
Vietnamese	khổ / Bất toại
Glossary of Buddhism

Dukkha (Pāli; Sanskrit: duḥkha; Tibetan: སྡུག་བསྔལ་ sdug bsngal, pr. "duk-ngel") is an important Buddhist concept, commonly translated as "suffering", "pain" or "unsatisfactoriness". It refers to the fundamental unsatisfactoriness and painfulness of mundane life, and inspires the Four Noble Truths and nirvana doctrines of Buddhism. The term is also found in scriptures of Hinduism, such as the Upanishads, in discussions of moksha (spiritual liberation).

Dukkha (Pali; Sanskrit duḥkha) is a term found in ancient Indian literature, wherein states Monier-Williams, it means anything that is "uneasy, uncomfortable, unpleasant, difficult, causing pain or sadness". It also refers to a concept in Indian religions about the nature of life that innately includes the "unpleasant", "suffering," "pain," "sorrow", "distress", "grief" or "misery." The term Dukkha does not have a one word English translation, and embodies diverse aspects of unpleasant human experiences. It is opposed to the word sukha, meaning "happiness," "comfort" or "ease."

The word is derived from Aryan terminology for the axle hole, referring to an axle hole which is not in the center and leads to a bumpy, uncomfortable ride. Winthrop Sargeant,

The ancient Aryans who brought the Sanskrit language to India were a nomadic, horse- and cattle-breeding people who travelled in horse- or ox-drawn vehicles. Su and dus are prefixes indicating good or bad. The word kha, in later Sanskrit meaning "sky," "ether," or "space," was originally the word for "hole," particularly an axle hole of one of the Aryan's vehicles. Thus sukha … meant, originally, "having a good axle hole," while duhkha meant "having a poor axle hole," leading to discomfort.

Joseph Goldstein, American vipassana teacher and writer, explains the etymology as follows:

The word dukkha is made up of the prefix du and the root kha. Du means “bad” or “difficult.” Kha means “empty.” “Empty,” here, refers to several things—some specific, others more general. One of the specific meanings refers to the empty axle hole of a wheel. If the axle fits badly into the center hole, we get a very bumpy ride. This is a good analogy for our ride through saṃsāra.

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Wikipedia