Definition of phlegm for English Language Learners. : 1  a thick, yellowish liquid that is produced in the nose and throat especially when a person has a cold. : 2  calmness in a difficult or unpleasant situation.
Kneecap (Patellar) Subluxation. A subluxing patella (kneecap) is a temporary, partial dislocation of the kneecap from its normal position in the groove in the end of the thigh bone (femur). This groove is located between two bumps at the end of the thigh bone called the femoral condyles.
Patellar luxation is a common, mildly to severely painful condition in domestic dogs. Basically, the patella (kneecap) slips out of place for some reason, resulting in lameness, weakness and pain.