As nouns the difference between terms and polymethine
is that terms is while polymethine is (organic chemistry) a compound made up from an odd number of methine groups bound together by alternating single and double bonds.
terms
English
Noun
(head)
Statistics
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polymethine
Noun
(
en noun)
(organic chemistry) A compound made up from an odd number of methine groups bound together by alternating single and double bonds.
See also
* polyene (a similar compound with an even number of methine groups)