The spelling of the word "planaea" is tricky because of its unusual combination of letters. It is pronounced /pləneɪə/, with the first syllable being unstressed and pronounced with the schwa sound /ə/. The second syllable has a long vowel sound /eɪ/ and the final syllable ends with the "uh" sound /ə/. The "a" following the letter "n" is pronounced like an "uh" sound, which can be confusing. Overall, the word is pronounced as "pluh-nay-uh."