Reststrahl
/ˈrɛstʃtrɑːl/(also Restrahl) Physics
noun
= Reststrahlen. Only in attributive use.
Origin
1930s; earliest use found in Journal of Applied Physics. From German Reststrahl-, combining form (in e.g. Reststrahlfrequenz, Reststrahlbande) of Reststrahlen Reststrahlen. Compare the rare German singular form Reststrahl.