local oscillator vs oscillator

local oscillator and oscillator both are nouns.

Word	Noun	Adjective	Verb	Adverb
local oscillator	Yes	No	No	No
oscillator	Yes	No	No	No

As nouns, oscillator is a hypernym of local oscillator; that is, oscillator is a word with a broader meaning than local oscillator:

local oscillator: an oscillator whose output heterodynes with the incoming radio signal to produce sum and difference tones
oscillator: generator that produces sonic oscillations or alternating current

local oscillator (noun)	oscillator (noun)
an oscillator whose output heterodynes with the incoming radio signal to produce sum and difference tones	generator that produces sonic oscillations or alternating current