skyrocket vs visual signal

skyrocket and visual signal both are nouns.

Word	Noun	Adjective	Verb	Adverb
skyrocket	Yes	No	Yes	No
visual signal	Yes	No	No	No

As nouns, visual signal is a hypernym of skyrocket; that is, visual signal is a word with a broader meaning than skyrocket:

skyrocket: propels bright light high in the sky, or used to propel a lifesaving line or harpoon
visual signal: a signal that involves visual communication

skyrocket (noun)	visual signal (noun)
sends a firework display high into the sky	a signal that involves visual communication
propels bright light high in the sky, or used to propel a lifesaving line or harpoon

skyrocket (verb)	visual signal (verb)
shoot up abruptly, like a rocket