from
The Collaborative International Dictionary of English v.0.48
Lautverschiebung \Laut"ver*schie`bung\
(lout"f[e^]r*sh[=e]`b[oo^]ng), n.; pl. {Lautverschiebungen}
(lout"f[e^]r*sh[=e]`b[oo^]ng*en). [G.; laut sound +
verschiebung shifting.] (Philol.)
(a) The regular changes which the primitive Indo-European
stops, or mute consonants, underwent in the Teutonic
languages, probably as early as the 3d century b. c.,
often called the {first Lautverschiebung}, {sound
shifting}, or {consonant shifting}.
(b) A somewhat similar set of changes taking place in the
High German dialects (less fully in modern literary
German) from the 6th to the 8th century, known as the
{second Lautverschiebung}, the results of which form the
striking differences between High German and The Low
German Languages. The statement of these changes is
commonly regarded as forming part of {Grimm's law},
because included in it as originally framed.
[Webster 1913 Suppl.]