"prototype" seems to fit.
The root word of "experimental" is "experiment," which comes from the Latin word "experimentum," meaning a test or trial.
experimental
False is a five letter word meaning fake.
A four letter word meaning not kosher is: tref
Flush is a five letter word meaning wealthy.
A five letter word meaning peace is quiet or amity.
What is a nine letter word meaning very tidy
Tardy is a five letter word meaning late.
A six letter word that has the same meaning of 'rue' is regret.
a six letter word meaning not attractive: SO UGLY!
The word pine can have that meaning.
The second letter of the seven letter word meaning "one-fourth" is "u." The word is "quarter."u as in quarter