pilot light vs gas jet

pilot light and gas jet both are nouns.

Word	Noun	Adjective	Verb	Adverb
pilot light	Yes	No	No	No
gas jet	Yes	No	No	No

As nouns, gas jet is a hypernym of pilot light; that is, gas jet is a word with a broader meaning than pilot light:

pilot light: small auxiliary gas burner that provides a flame to ignite a larger gas burner
gas jet: burner such that combustible gas issues from a nozzle to form a steady flame

Other hypernyms of pilot light include gas burner.

pilot light (noun)	gas jet (noun)
indicator consisting of a light to indicate whether power is on or a motor is in operation	burner such that combustible gas issues from a nozzle to form a steady flame
small auxiliary gas burner that provides a flame to ignite a larger gas burner