* Dlr index falls after leading central banks slash rates

* Dlr/yen back above 100 yen as uneasy calm descends

* Stock markets cut losses as panic selling eases off

(recasts, adds quotes, update prices, changes byline)

By Veronica Brown

LONDON, Oct 8 (Reuters) - The dollar fell against a basket of currencies on Wednesday after leading global central banks announced rate cuts in an effort to stem haemorrhaging markets engulfed in the worst financial crisis since the 1930s.

The Fed said it was cutting its key federal funds rate by 50 basis points to 1.5 percent. China, the European Central Bank (ECB) and central banks in Britain, Canada, Sweden and Switzerland also cut rates in the coordinated response which analysts had been demanding.

Prior to the central bank action, currency investors had pushed the Japanese yen to multi-year highs against the euro and high yielding currencies in a rush to offload risk as global stock markets plummeted.

Analysts said the long-called for central bank action may mark a turning point in investors approach to risk, which could see the U.S. currency fall further as it had previously benefitted from repatriation and dollar-funding flows.