The spelling of the phrase "was unison" is quite straightforward, once you understand the phonetic transcription. In IPA, "was" would be transcribed as /wɒz/, which is pronounced as "wahz." Similarly, "unison" is transcribed as /ˈjuːnɪsən/, which is pronounced as "YOO-ni-suhn." Therefore, "was unison" would be spelled as it sounds, with the "wahz" sound followed by "YOO-ni-suhn." Remembering the pronunciation in IPA can help with proper spelling and understanding of the phrase.