the.com/deep freeze

means To freeze something at very low temperature for long-term storage, or more broadly, to put a plan, relationship, or situation on indefinite, unmoving hold.

from Literal first: 'deep freeze' named the commercial freezers of the 1930s-40s that chilled food far below ordinary icebox temperatures, deep enough to halt decay almost entirely. The brand-like phrase (echoing trademarks such as Deepfreeze) stuck as the generic term. From there it thawed into metaphor by the mid-20th century — Cold War diplomats and office memos alike started describing stalled talks, frozen funds, or shelved projects as being 'in deep freeze,' borrowing the appliance's sense of suspended animation for anything put on indefinite ice.