gereinigten

Gereinigten is the declined past participle form of the German verb reinigen, meaning to clean or purify. When used attributively to describe a noun, it indicates that the noun has undergone cleaning or purification. In German, attributive adjectives are declined to reflect the noun’s gender, number, and case, and after definite determiners such as der, die, das, den, dem, and des they commonly take the weak ending -en in many forms.

Examples of common patterns with a definite article include:

- der gereinigte Filter (masculine singular nominative)

- den gereinigten Filter (masculine singular accusative)

- das gereinigte Wasser (neuter singular nominative/accusative)

- die gereinigten Filter (plural nominative/accusative)

- der gereinigten Lampe (feminine singular dative)

Note that the endings change with different articles and cases; for instance, feminine singular in the dative uses der gereinigten Lampe, and plural in accusative uses die gereinigten Filter. With indefinite articles or without an article, the endings differ (e.g., ein gereinigter Filter; gereinigtes Wasser; gereinigte Filter).

Gereinigten is primarily an attributive form. In predicate or finite-verb constructions, the past participle uses reinigt or gereinigt, as in Der Filter wurde gereinigt (The filter was cleaned) or Das Wasser ist gereinigt (The water is cleaned). The base participle is gereinigt, while gereinigten represents its declined, descriptive use in noun phrases.

Etymology: it derives from reinigen, with the standard past participle gereinigt, and the -en ending appearing in the attributive, declined form.