elapsed time vs OWLT

elapsed time and OWLT both are nouns.

Word	Noun	Adjective	Verb	Adverb
elapsed time	Yes	No	No	No
OWLT	Yes	No	No	No

As nouns, OWLT is a hyponym of elapsed time; that is, OWLT is a word with a more specific, narrower meaning than elapsed time:

elapsed time: the time that elapses while some event is occurring
OWLT: the elapsed time it takes for light (or radio signals) to travel between the Earth and a celestial object

Other hyponyms of elapsed time include one-way light time, round-trip light time, RTLT.

elapsed time (noun)	OWLT (noun)
the time that elapses while some event is occurring	the elapsed time it takes for light (or radio signals) to travel between the Earth and a celestial object