an inflammatory disease of connective tissue with variable features including fever and weakness and fatigability and joint pains and skin lesions on the face or neck or arms
"After weeks of high fevers, severe fatigue, and painful swelling in her joints, the doctor diagnosed her with sle."
Initialism of systemic lupus erythematosus.
"The doctor explained that her fatigue was a common symptom of SLE, which is an autoimmune disease affecting multiple organ systems."
In plain English: A sle is an old-fashioned word for someone who acts smugly and tries to look better than everyone else around them.
"The sle drifted silently down the snow-covered hill during the winter storm."