Oxymoronic (oxy) candlesticks often appear at significant levels in a chart and can indicate increased probabilities of directional moves.
Typically, green candles are hollow and red candles are filled. An oxymoronic candle is colored bullishly but filled bearishly (solid green) or vice versa (hollow red).
Oxy flags occur when: 1) Price gaps up and closes lower than the open but above the last close. A solid green (or black) candle is bearish. 2) Price gaps down and closes higher than the open but below the last close. A hollow red candle is bullish.
An oxy candle indicates one of three things: 1) Price is going up (bullish oxy) 2) Price is going down (bearish oxy) 3) Price will return to this level (either)
#1 and #2 are the default meaning. If those don't play out then look for #3.
As is the case with most indicators, it is best not to use this indicator in isolation, but to combine it with other forms of analysis to increase your probabilities and to identify significant levels.