platter vs L-P

platter and L-P both are nouns.

Word	Noun	Adjective	Verb	Adverb
platter	Yes	No	No	No
L-P	Yes	No	No	No

As nouns, L-P is a hyponym of platter; that is, L-P is a word with a more specific, narrower meaning than platter:

platter: sound recording consisting of a disk with a continuous groove; used to reproduce music by rotating while a phonograph needle tracks in the groove
L-P: a long-playing phonograph record; designed to be played at 33.3 rpm

Other hyponyms of platter include LP, 78, seventy-eight.

platter (noun)	L-P (noun)
a large shallow dish used for serving food	a long-playing phonograph record; designed to be played at 33.3 rpm
sound recording consisting of a disk with a continuous groove; used to reproduce music by rotating while a phonograph needle tracks in the groove