Suffering
Dukkha is a Pali word, which appears in Sanskrit as duḥkha, and it is most often translated as “pain,” “suffering,” “stress,” or “dis-ease” (and as an adjective, “painful, stressful”). The concept of dukkha is one of the fundamental teachings of Buddhism.
The Four Noble Truths refer to and express the basic orientation of Buddhism in a short expression: we crave and cling to impermanent states and things, which are dukkha, “incapable of satisfying” and painful. This craving keeps us caught in samsara,the endless cycle of repeated rebirth and dying again, and the dukkha that comes with it.
It is because we see ourselves as separate from other things that we desire them, or are repulsed by them. All emotions are pain because they involve dualism.
Buddhism – Suffering in Christianity
References: https://www.oxfordbibliographies.com/view/document/obo-9780195393521/obo-9780195393521-0127.xml#:~:text=Dukkha%20is%20a%20Pali%20word,the%20fundamental%20teachings%20of%20Buddhism.&text=99–100%2C%20cited%20under%20In%20Buddhist-Christian%20Dialogues