The spelling of the word "equa" can be explained through IPA phonetic transcription. The word is pronounced as "ˈiːkwə" where the first syllable is stressed. The "e" represents a long "ee" sound, and "qu" is pronounced as "kw". The final "a" is pronounced as "uh", which is a schwa sound. This spelling is derived from the Latin word "aequus" meaning "equal". In English, "equa" is not a commonly used word, but it might appear in scientific or mathematical contexts to signify "equal".