The spelling of the word "Easterday" is straightforward once you understand its pronunciation. In IPA phonetic transcription, it is spelled /ˈiːstərdeɪ/. The first syllable is pronounced like "ee" and the second syllable like "ster." The final syllable is pronounced like "day." Therefore, the correct spelling is "Easterday," referring to the day of the Christian holiday Easter. This word is often used to refer to the day when Easter is celebrated, which usually falls on a Sunday in the spring.
There is no commonly-recognized word "Easterday" in the English language. It appears to be a combination of two separate words, "Easter" and "day".
"Easter" refers to the Christian holiday that celebrates the resurrection of Jesus Christ from the dead. The word "Easter" has its roots in Old English, specifically from the name of a Germanic pagan festival called "Eostre". The festival marked the arrival of spring and the goddess Eostre, who symbolized fertility and rebirth. The Christian holiday of Easter gradually replaced this pagan festival but retained the same timing and many similar elements.
"On the other hand, "day" is a common word that originates from the Old English word "dæg". "Dæg" has Germanic roots and is related to the word "Tag" in German and "dag" in Dutch.