Mortality displacement denotes a temporary increase in the mortality rate (number of deaths) in a given population, also known as excess mortality or an excess mortality rate. It is usually attributable to environmental phenomena such as heat waves, cold spells, epidemics and pandemics, especially influenza pandemics, famine or war.

https://en.wikipedia.org/wiki/Mortality_displ...

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We estimated the excess mortality for each country by comparing the number of people who died from all causes this year with the historical average during the same period.

https://www.nytimes.com/interactive/2020/04/2...

Some heat-related deaths may occur in people whose health is already compromised, resulting in a decrease in the expected number of deaths following an initial increase, a phenomenon referred to as mortality displacement or “harvesting”

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC...

Mortality displacement of heat-related deaths: a comparison of Delhi, São Paulo, and London.

Hajat S1, Armstrong BG, Gouveia N, Wilkinson P.

London School of Hygiene & Tropical Medicine

Abstract

BACKGROUND:

Mortality increases with hot weather, although the extent to which lives are shortened is rarely quantified. We compare the extent to which short-term mortality displacement can explain heat deaths in Delhi, São Paulo, and London given contrasting demographic and health profiles.

METHODS:

We examined time-series of daily mortality data in relation to daily ambient temperature using Poisson models and adjusting for season, relative humidity, rainfall, particulate air pollution, day of the week, and public holidays. We used unconstrained distributed lag models to identify the extent to which heat-related excesses were followed by deficits (mortality displacement).

(...)

CONCLUSIONS:

Heat-related short-term mortality displacement was high in London but less in Delhi, where infectious and childhood mortality still predominate.

https://www.ncbi.nlm.nih.gov/pubmed/16135936

Estimating Mortality Displacement During and After Heat Waves

Ben Armstrong, Antonio Gasparrini, Shakoor Hajat

American Journal of Epidemiology, (...)

The proportion of excess deaths occurring as a result of hot weather that are brought forward by only a short time (“displaced”) is important but not easy to estimate. A recent proposal by Saha et al. (Am J Epidemiol. 2014;179(4):467–474) was to estimate this using a “displacement ratio” equal to the sum of deficits of daily deaths below an expected baseline divided by the sum of excesses over all days during and up to 15 days after a heat wave. (...)

#10: My understanding of the alternative "mortality [dis]placement" is that these refer to persons who were likely to die anyway but who then died earleir as a result of a specific disease or cirumstances such as extreme heat in summer.

Ja. Mortality displacement bezeichnet im Fachdiskurs offenkundig die "Verschiebung" der Mortalität, wenn auf einen krisenhaften, kurzfristigen Anstieg (excess mortality/Übersterblichkeit) eine reduzierte Mortalität (Untersterblichkeit) folgt. Die von Wikipedia behauptete Synonymität (mortality displacement=excess mortality) ist mE zu kurz gegriffen.