What terminology would you use to indicate a painful condition?

The suffix that denotes a painful condition is commonly represented by "-dynia." This term originates from the Greek word "odynē," meaning pain. In medical terminology, this suffix is attached to root words to specify the location or type of pain, such as in "gastrodynia," which refers to stomach pain.

In contrast, the other choices relate to different concepts: "-cytic" pertains to cells (as seen in words like "erythrocytic," related to red blood cells), "-dipsia" refers to thirst (as in "polydipsia," which indicates excessive thirst), and "-derma" is associated with skin (such as in "dermatitis," which refers to skin inflammation). Therefore, "–dynia" is the correct choice for indicating a painful condition, as it specifically encapsulates the concept of pain in its meaning.