The term 'oppose successfully' can be summarized by the crossword solution 'THWART, ' which is a six-letter word meaning to prevent or obstruct someone from achieving a goal. It is often used in a negative context, as it implies that someone is actively trying to stop another person from succeeding. Thwarting can be done through physical means, such as blocking a path, or through psychological means, such as discouraging someone from pursuing their goals.