Editing Grimm's law (section)

==Behaviour in consonant clusters==

When two obstruents occurred in a pair, the first was changed according to Grimm's law, if possible, while the second was not. If either of the two was voiceless, the whole cluster was devoiced, and the first obstruent also lost its labialisation, if it was present.

Most examples of this occurred with obstruents preceded by *s (resulting in *sp, *st, *sk, *skʷ), or obstruents followed by *t (giving *ft, *ss, *ht, *ht) or *s (giving *fs, *ss, *hs, *hs). The latter change was frequent in suffixes, and became a phonotactic restriction known as the [[Germanic spirant law]]. This rule remained productive throughout the Proto-Germanic period. The cluster *tt became *ss (as in many Indo-European daughter languages), but this was often restored analogically to *st later on.

Examples with preceding *s:

{| class="wikitable"
! Non-Germanic examples
! Change
! Germanic examples
|-
| Latin: ''spuere,'' Lithuanian: ''spjáuti''
! *sp
| English: ''spew,'' West Frisian: ''spije'', Dutch: ''spuwen'', German: ''speien,'' Danish, Norwegian, Swedish: ''spy,'' Icelandic: ''spýja'', Faroese: ''spýggja'', Gothic: ''speiwan''
|-
| Latin: ''stāre'', Irish: ''stad'', Sanskrit: ''sta'', Russian: стать (''stat'''), Lithuanian: ''stoti'', Persian: {{lang|fa|ايستادن}} (''istâdan'')
! *st
| English: ''stand'', Icelandic, Faroese, Norwegian: ''standa'', Gothic: ''standan''; West Frisian: ''stean'', Dutch: ''staan'', German: ''stehen'', Danish, Swedish: ''stå''
|-
| <!--- Sanskrit: ''krdhuh,'' Latin: ''curtus,'' Irish: ''gearr'',---> Lithuanian: ''skurdus''
! *sk
| English: ''short'', Old High German: ''scurz'', Icelandic: ''skorta''
|-
| Irish: ''scéal''
! *{{PIE|skʷ}}
| English: ''scold,'' Icelandic: ''skáld,'' Norwegian: ''skald''; West Frisian: ''skelle'', Dutch: ''schelden'', German: ''schelten''
|}

* Some linguists dispute the origin of the word "scold", but [[Julius Pokorny]], among others, proposed *skʷetlo as the assumed root.
* Several languages, including [[English language|English]], later have an unrelated change {{IPA|/sk/}} > {{IPA|/ʃ/}} (or > {{IPA|/sx/}} in the case of [[Dutch language|Dutch]]).

Examples with following *t:

{| class="wikitable"
! Non-Germanic examples
! Change
! Germanic examples
|-
| Ancient Greek: κλέπτης (''kleptēs''), Old Prussian: ''au-klipts'' "hidden"
! *pt→ft
| Gothic: ''hliftus'' "thief"
|-
| Latin: ''atta'', Greek: ἄττα (''átta'')
! *tt→tt
| Old High German: ''atto'', Gothic: ''atta'' "father"
|-
|  Ancient Greek: ὀκτώ (''oktō''), Irish: ''ocht'', Latin: ''octō'' <!---Lithuanian: ''aštuoni,'' Sanskrit: अष्ट (''aṣṭa'') --->
! *kt→ht
| English: ''eight'', West Frisian, Dutch, German: ''acht'', Gothic: ''ahtáu'', Icelandic: ''átta''
|-
| Irish: ''anocht'', Latin: ''nox, noct-'', Greek: νύξ, νυκτ- (''núks, nukt-),'' Sanskrit: नक्तम् (''naktam''), Lithuanian: ''naktis,'' Hittite (genitive): ''nekuz'' (pronounced ''{{IPA|/nekʷts/|}}'') <!--- Russian: ночь (''noch''),  --->
! *{{PIE|kʷt}}→ht
| English: ''night'', West Frisian, Dutch, German: ''Nacht'', Gothic: ''nahts'', Icelandic: ''nótt''
|}

* Icelandic ''nótt'' {{IPA|is|nouht|}} comes from Old Norse ''nǫ́tt'', ''nátt'', from Proto-Germanic ''*naht-''. The Germanic ''*ht'' regularly becomes Old Norse ''tt'', and this then becomes preaspirated in Icelandic. Thus, the {{IPA|[h]}} of the modern Icelandic form is not Germanic {{IPA|/h/}}'s direct descendant. The same ancestry holds for Icelandic ''átta'''s {{IPA|/tt/}} as well.{{cn|date=February 2025}}