a device consisting of a bar or wheel with a set of angled teeth in which a cog or tooth engages, allowing motion in one direction only

a ratchet screwdriver

a situation or process that is perceived to be changing in a series of irreversible steps

the upward ratchet of property taxes

operate by means of a ratchet

a ratcheted quick release system

a smooth ratcheting action

cause something to rise or fall as a step in a steady and irreversible process

the Bank of Japan ratcheted up interest rates again

investors should ratchet down their expectations for earnings growth into single-digit territory

both countries have ratcheted back the Cold War era rhetoric

(especially in African American usage) unattractively coarse, disreputable, or unfashionable (typically used of a woman)

she looks so ratchet in that dress