When there is a shorter synonymous word (as inamongst/among), the form with-st is generally considered more formal, old-fashioned or affected in American English; whereas both are usually interchangeable in British English.
However,against is distinct in meaning fromagain, andmidst is used in some contexts distinctly frommid.
FromProto-Germanic*-þiz. The-s- is the result of a wrong segmentation ofstem and suffix of a noun in cases where the stem of the noun ended with-s-. For example: a word likeDutchvorst(“frost”) could be interpreted asvors+t or asvor+st. This suffix existed already inGothic (𐌰𐌽𐍃𐍄𐍃(ansts), from*𐌿𐌽𐌽𐌰𐌽(*unnan)).[1]
In the present tense, the suffix becomes-t afters, ß, x, z:duschießt. Aftersch the spelling-t is standard only in Austria and South Tyrol, but the according pronunciation is common in most regions:duwäschstorwäscht.
The suffix becomes-est afterd, t:duwartest. However, strong verbs with a vowel change have-st:durätst. In obsolete usage the form-est was employed more freely also after other sounds.
In the strong past tense,-est is used aftersibilants:duschossest. However, when the preceding vowel is long the form-t is possible alternatively:duaßestoraßt. Afterd, t the forms-est and-st are used in free variation:durittestorrittst.
Attributive superlatives are declined like other adjectives.Predicative andadverbial superlatives generally take the particleam before them and are accordingly declined in the neuter dative singular. Some adjectives/adverbs also have basic forms in-st, but these are generallylexicalised.
The suffix becomes-est after sibilantss, sch, ß, x, z and afterd, t when the adjective has final stress:derkürzeste,weiteste (thoughder kürzte, weitste may be heard colloquially and the same is standard indergrößte). When the last vowel is/ə/ or unstressed/ɪ/ the short form is used:dergeeignetste,sympathischste. After other unstressed vowels both ways are possible:derelendesteorelendste.
The forms-st and-est are also both possible after stressed final vowels and after consonant clusters (except those involving-r-). Thus:derneuesteorneuste,derschlankesteorschlankste. The formal language prefers the long forms while the vernacular prefer the short ones.
From-s(adjective-forming suffix) +-t(locative suffix) in the Old Hungarian period. The adverbial sense of the locative suffix-t can be shown only in this-st morpheme.[1]
^Papp, Ferenc (ed.).A magyar nyelv szóvégmutató szótára (’Reverse-Alphabetized Dictionary of the Hungarian Language’). Budapest: Akadémiai Kiadó, 1994, p. 495.
The expected form would be-scht as still inbescht(“best”) andmeescht(“most”). The form-st is native in the northern third of Luxembourg and spread southwards, probably in part because the suffix is used in positions where/ʃ/ otherwise does not occur, and in part under the reinforcing influence of standardGerman.
