The spelling of the word "re achy" can be explained using IPA phonetic transcription. The "re" sound is transcribed as /ri:/, while the "a" sound is transcribed as /eɪ/. The "ch" sound is represented as /tʃ/, and the "y" sound is transcribed as /i/. This results in the complete phonetic transcription of the word as /ri: eɪtʃi i/. Overall, understanding the phonetic transcription of words can help individuals better understand spelling and pronunciation.