jam tomorrow

Proposed by a contributor, not yet supported by evidence.

Meaning · English

Promised benefits that never actually materialize

Nghĩa · Tiếng Việt

Lợi ích được hứa nhưng không bao giờ thực sự hiện thực

Machine-translated — suggest a fix

Literally: jam served tomorrow
Where it’s used: Used Widespread English

Examples

There is also an element of ‘ jam tomorrow’ about some of Mr Lamont's measures.
Mr Lamont forecasts that the economy will be growing at the rate of three per cent per year in 12 months ' time; he would have carried more conviction, if he had not made the same ‘ jam tomorrow’ forecast a year ago.

British National Corpus sentence via the MAGPIE corpus (CC BY 4.0, retrieved 2026-07-30)

Sources & notes

Listed in Wiktionary’s “English idioms” category (retrieved 2026-07-29); definition pending editorial review. Definition drafted by AI (@cf/meta/llama-3.3-70b-instruct-fp8-fast) and auto-approved by rule on 2026-07-31; pending editor spot-check.

Common questions

What does “jam tomorrow” mean?

Promised benefits that never actually materialize Literally: jam served tomorrow

Is “jam tomorrow” formal or informal?

No register label has been reviewed yet — treat it as neutral and check the usage notes above.