I'm not sure what I'd call that person...but I would suggest you check a dictionary. "Lenghtly" is not a word, and you've misspelled "explanation."
A person who uses long words and lengthy explanations can be referred to as verbose or loquacious.
A person who uses a lot of words can be referred to as verbose or loquacious.
A person who uses sophisticated words is often called eloquent or articulate, with a strong command of language and vocabulary.
A person who studies the origins of words is called an etymologist. They investigate the history and development of words, tracing their roots and understanding how their meanings have changed over time.
A person who plays with words is commonly known as a wordsmith or a wordsmith and is often skilled in using language creatively and cleverly.
Sesquipedalian
A person who uses sophisticated words is often called eloquent or articulate, with a strong command of language and vocabulary.
lexicologist.
Philologist
A bully
a sesquipediophile
Educated.
A person who develops or invents new words is called a "neologist" or a "lexicographer." They may also be referred to as a "word inventor" or a "lexiphanic."
A person who plays with words is commonly known as a wordsmith or a wordsmith and is often skilled in using language creatively and cleverly.
A walking dictionary?
Amateur / apprentice, many other words.
George Bush
this is a person who wants to learn and study new words, in other words a smart person!!