al·​lo·​isom·​er·​ism | \ˌalōˌīˈs-\
plural -s

Definition of alloisomerism 

1 : isomerism not explainable by the ordinary structural formulas

2 : cis-transisomerism

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First Known Use of alloisomerism

1886, in the meaning defined at sense 1

History and Etymology for alloisomerism

all- + isomerism

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The first known use of alloisomerism was in 1886

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something that serves to warn or remind

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