I believe they mean that the random variables have a common support. For example, if X ~ Unif[0,2] and Y ~ Unif[1,3], then their respective PDF's overlap in the interval [1,2], meaning the only interval where both X and Y can have common values is [1,2]. To illustrate, below is a representation of the supports of X and Y, below which is a representation of the real line.
1 Thyroid cancer is a malignant tumor of the thyroid gland. 2  Symptoms of thyroid cancer include swelling in the neck (goiter), neck pain, hoarseness, swallowing and breathing problem, swollen lymph gland in the neck.
Enlarged or swollen glands, Swelling (Face), Swelling (Jaw) and Tender glands WebMD Symptom Checker helps you find the most common medical conditions indicated by the symptoms enlarged or swollen glands, swelling (face), swelling (jaw) and tender glands including Mumps, Swollen glands, and Cellulitis. There are 20 conditions associated with enlarged or swollen glands, swelling (face), swelling (jaw) and tender glands. The links below will provide you with more detailed information on these medical conditions from the WebMD Symptom Checker and help provide a better understanding of causes and treatment of these related conditions.