Capable of being dilated, expanded, or stretched; able to increase in size or volume.
From dilate + -able (capable of). Dilate derives from Latin dilatare (to spread out), from di- (apart) + latus (wide). The suffix -able means 'capable of being.'
Your pupils are dilatable, your blood vessels are dilatable, and certain materials like rubber are dilatable—it's a property that's essential for everything from survival to engineering.
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