A measure of the extent to which something is treatable(noun)
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Use "treatability" in a sentence
"Throughout the campaign, the motive was the same: to awaken "public consciousness to the symptoms and treatability" of depression."
"However, these tests do not describe particle size characteristic of a suspension, an important parameter which greatly influences treatability of a water and, hence, filter efficiency."
"The design of roughing and slow sand filters is usually conservative, i.e., it allows uncertainties with respect to raw water quality and treatability."