Words that really are opposite to each other, would be words that just cannot be put together. For example, a "round square" could not happen because squares are not round.
w ɜː d z WORD_BOUNDARY ð æ t WORD_BOUNDARY ɹ iə l i WORD_BOUNDARY ɑ ɹ WORD_BOUNDARY ɑ p ə z ɪ t WORD_BOUNDARY t ʊ WORD_BOUNDARY iː t̠ʃ WORD_BOUNDARY ʌ ð ə ɹ WORD_BOUNDARY w ʊ d WORD_BOUNDARY b iː WORD_BOUNDARY w ɜː d z WORD_BOUNDARY ð æ t WORD_BOUNDARY d̠ʒ ʌ s t WORD_BOUNDARY k æ n ɑ t WORD_BOUNDARY b iː WORD_BOUNDARY p ʊ t WORD_BOUNDARY t ə ɡ ɛ ð ə ɹ WORD_BOUNDARY f ɔ ɹ WORD_BOUNDARY ɛ ɡ z æ m p ə l WORD_BOUNDARY ʌ WORD_BOUNDARY ɹ aʊ n d WORD_BOUNDARY s k w ɛ ɹ WORD_BOUNDARY k ʊ d WORD_BOUNDARY n ɑ t WORD_BOUNDARY h æ p ə n WORD_BOUNDARY b ɪ k ʌ z WORD_BOUNDARY s k w ɛ ɹ z WORD_BOUNDARY ɑ ɹ WORD_BOUNDARY n ɑ t WORD_BOUNDARY ɹ aʊ n d WORD_BOUNDARY