* Thai baht appreciates over half a percent * S.Korea"s won hits lowest since September * Malaysian c.bank cuts 2021 growth forecast By Sameer Manekar Aug 13 (Reuters) - Thailand"s baht edged up among mostly muted Asian currencies on Friday, after a short-lived retreat in the dollar this week even as COVID-19 worries capped gains, while South Korea"s won fell for a fifth straight session to hit a 10-month low. Most Asian currencies were set to end the week lower, with South Korea"s won the top loser and on track to post its worst weekly performance since March last year, while Thai baht was an outlier, gaining more than half a percent. The baht, trading after a public holiday on Thursday, added 0.6% to mark its best day since mid-April, as investors rushed in after the U.S. dollar slipped on Wednesday following a tame U.S. inflation reading. The dollar index, which measures the greenback against a basket of currencies, stood firm at 92.966 on Friday, after sliding to 92.800 on Wednesday and providing a temporary respite to Asia"s risk-sensitive markets. "When the Thai market entered the holiday period on Wednesday, lots of people were caught off guard from the falling dollar, which moved against their short Thai baht positions," Poon Panichpibool, Markets Strategist at Krung Thai Bank said. "It"s just a short-term break for the baht; still expect it to weaken further due to the worsening COVID-19 situation tmsnrt.rs/2FkV6wq in the country which could urge more selling of Thai assets from foreign investors." In South Korea, the won declined more than half a percent, down for a fifth consecutive day as the country battles to contain the spread of the more contagious Delta variant of the coronavirus. The country also saw massive foreign outflows of 1,667.3 billion won ($1.43 billion) worth of shares on the main board on Friday, further hurting the sentiment. Malaysian equities slipped into negative territory, paring earlier gains, as the central bank lowered its economic growth forecast here for 2021 to between 3% and 4% from an earlier forecast of between 6% and 7.5%. The ringgit was largely unchanged despite Bank Negara Malaysia flagging the likelihood of the currency being "exposed to periods of heightened volatility" from global and domestic economic recovery uncertainty. Among equities, Thai benchmark index and India"s Nifty 50 were the sole gainers, adding half a percent each. HIGHLIGHTS: ** Indonesian 10-year benchmark yields rise 5.1 basis points to 6.392% ** Thailand sees second day of record coronavirus cases ** Singapore"s Olam International considering raising 2 billion pounds ($2.76 billion) via food ingredients London IPO - sources Asia stock indexes and currencies at 0430 GMT COUNTRY FX RIC FX DAILY % FX YTD % INDEX STOCK STOCK S S YTD DAILY % % Japan -0.02 -6.49 0.06 2.14 China +0.02 +0.78 -0.25 1.23 India -0.02 -1.62 0.49 17.62 Indonesia -0.03 -2.39 -0.09 2.59 Malaysia -0.07 -5.05 -0.07 -7.76 Philippines -0.06 -4.78 -0.17 -8.32 S.Korea -0.61 -7.03 -1.35 10.15 Singapore -0.04 -2.73 -0.72 11.11 Taiwan -0.06 +2.32 -1.08 15.62 Thailand +0.21 -9.95 0.29 6.05 ($1 = 0.7242 pounds) (Reporting by Sameer Manekar in Bengaluru; Editing by Himani Sarkar)