* Gold briefly pierces 200-day moving average, but then loses ground
* Dollar pares losses against euro
* GRAPHIC-Gold vs currencies: http://link.reuters.com/cyv95s (Updating to recast, update prices, add comment)
By Josephine Mason and Jan Harvey
NEW YORK/LONDON, Oct 21 (Reuters) - Gold fell almost 1 percent on Wednesday for its biggest one-day loss in three weeks on technical selling and long liquidation as the dollar recovered ground versus the euro amid uncertainty over the timing of a Federal Reserve interest rate hike.
Bullion briefly burst through a 200-day moving average around $1,175 per ounce on Wednesday for a sixth straight day before easing back more than $10 to a session low.
Its failure to hold above a long-term resistance undermined sentiment and increased selling pressure.
"Some longs are taking profits as gold has struggled to hold above the 200-day moving average, usually a significant technical level and often signals a medium term change in sentiment," said Tai Wong, director of base and precious metals trading for BMO Capital Markets in New York.
The dollar pared earlier losses to trade little changed against Europe's single currency as traders awaited the outcome of a European Central Bank policy meeting on Thursday. FRX/
The ECB is unlikely to adjust its 60-billion-euros per month asset purchase programme in October, but investors believe it may hint at more stimulus later this year.
Spot gold XAU= was down 0.8 percent at $1,167.6 an ounce at 3:34 p.m. EDT (1934 GMT), off a session high of $1,179.20.
U.S. gold futures GCv1 for December delivery settled down $10.0 an ounce, or 0.9 percent, at $1,167.1.
In July, speculation that U.S. interest rates would rise this year helped pressure gold to a 5-1/2-year low, but a raft of downbeat U.S. data and concerns over Chinese growth have since fuelled talk that the move may be postponed.
Rising rates tend to weigh on gold, as they lift the opportunity cost of holding non-yielding assets, while supporting the dollar, in which it is priced.
"Gold is just following U.S. (monetary policy)," Natixis analyst Bernard Dahdah said. "Gold has risen $75 since early September, based on expectations that a rate hike will happen in 2016, not the end of this year."
Among other precious metals, silver XAG= was down 1.3 percent at $15.77 an ounce, platinum XPT= was down 1.3 percent at $1,006 an ounce and palladium XPD= was down 2.7 percent at $679 per ounce.