-sch

See also: sch, Sch, Sch., sch-, and -'sch

Dutch

Etymology tree

Proto-Indo-European *-iskos

Proto-Germanic *-iskaz

Old Dutch -isc

Middle Dutch -sch

Dutch -sch

-sch

Occasionally used in deliberately archaising language; e.g. a product marketed to appeal to a sense of nostalgia may use a spelling such as Hollandsch instead of Hollands.
In some cases this archaising usage extends even to words ending in -s today which historically did not end in -sch at all. For example, some university sororities may include the word damesch (from dames, plural of dame (“lady”)): a completely made-up archaism, as the plural marker -s historically was never spelled -sch.

Contraction of -isch.

-sch

A suffix attached to names to produce eponymous adjectives: -ean, -ian, 's
die Boolesche/boolesche Algebra ― Boolean algebra

Words in -sch inflect like normal adjectives.
While the name generally remains capitalised with the spelling -'sch, it may alternatively be lowercased without the apostrophe (provided that the adjective is neither nominalised nor part of a fixed term).

Etymology tree

Proto-Indo-European *-iskos

Proto-Germanic *-iskaz

Old Dutch -isc

Middle Dutch -sch

-sch