"Painful engorgement" refers to a situation where a body part becomes swollen, usually due to excessive fluid or blood accumulation, and it causes discomfort or pain. Full definition
In this way you can gradually get your baby used to taking the bottle instead of the breast during the day and you can avoid painful engorgement on the job! (breastmilk.com)
To keep up your milk supply in both breasts — and prevent painful engorgement in one — it's important to alternate breasts and try to give each one the same amount of nursing time throughout the day. (kidshealth.org)
If this happens, to keep up your milk supply in both breasts (and prevent painful engorgement), alternate breasts and keep your baby on the first breast until it's soft, then move your baby to the second breast. (kidshealth.org)