Definition:
The word "melody" is a noun that refers to a series of musical notes that are arranged in a way that is pleasing to hear. It is often the main part of a song that you can hum or sing along to.
In more advanced contexts, "melody" can refer to the main theme of a piece of music, which can be contrasted with harmony (the combination of different musical notes played or sung at the same time).
Melodic (adjective): Relating to melody; having a pleasant sound.
Melodiously (adverb): In a way that is musical or pleasant to hear.
"Sing a different tune": This idiom means to change one's opinion or attitude about something.
"In tune": This phrase means to be in agreement or harmony with someone or something.
In summary, "melody" is a fundamental concept in music that refers to a sequence of notes that create a pleasant sound.