From Middle High German denne, tenne, from Old High German denna, a variant of danne (see dann). The functional split between denn and dann was prescribed only by the grammarians of the 18th century. Cognate with English then.
- for; because; since
- Ich möchte diese Hose kaufen, denn sie gefällt mir sehr. ― I'd like to buy these pants since I like them a lot.
- (after a comparative, archaic or dialectal) than
- Synonym: als
The normal conjunction after a comparative is als; denn is generally archaic. Only in two cases is it still found in contemporary German:
- before als meaning “as, like”, in order to avoid reduplication: Er war nie glücklicher denn als kleiner Junge. — “He was never happier than as a little boy.” This usage is formal.
- before je (“ever before”): Er ist glücklicher denn je. — “He is happier than ever before.” This usage is normal or only slightly formal. The combination als je is not common, but one can say als je zuvor.
- (in a question, modal particle) then, ever, but, now (used for emphasis or to express interest, surprise or doubt, or in rhetorical questions)
- Wo ist er denn? ― Where is he, then?/Where ever can he be?
- Wieso denn? ― How so, then?
- Was denn? ― But what?
- (rather rare) thus, so; (expresses a consequence; see usage notes)
- (colloquial, regional, Northern Germany) then, after that, in that case
Dann and denn are originally variants of the same word but came to be distinguished in modern German. Dann is an adverb with the basic meaning “then” (in the sense of “after that” or “in that case”). Denn is chiefly a conjunction meaning “because, for”. However, when denn is used as an adverb, the distinction from dann can be somewhat problematic.
- Dann and denn in questions:
- Denn is frequently used in questions to emphasize the questioner’s interest in the answer and often to express a degree of surprise:
- Wir machen jetzt Mittag. — Seid ihr denn schon fertig?
- We’re off to lunch now. — But are you done already?
- Dann is less frequent in questions, but it can express that the question is based on an assumption:
- Wir machen jetzt Mittag. — Seid ihr dann schon fertig?
- We’re off to lunch now. — So are you already done then?
- Dann and denn meaning “thus”:
- The normal words for “thus, so” expressing a consequence are also and (literary) somit. However, both dann and denn can also mean “thus”, chiefly when they are not the first word of the clause:
- Angesichts dieser widerstrebenden Einflüsse verlief die Entwicklung des Landes dann/denn in der Tat recht ungewöhnlich.
- Given these conflicting influences, the development of the country thus took indeed a rather peculiar course.
- The difference here is very vague. Denn may slightly emphasize that there is an actual logical consequence between both facts.
- Dann and denn in regional speech:
- Colloquially, the distinction may not be strictly followed. Particularly, dann is used in questions in parts of western Germany and denn is used for “then” in parts of northern Germany:
- Sin’ Se dann schon achtzehn? (“Are you even eighteen yet?”) — Rhineland
- Na, denn man los! (“So then let’s go!”) — Lower Saxony, Hamburg, etc.
- “denn” in Duden online
- “denn (Konjunktion)” in Duden online
- “denn” in Duden online
- “denn” in Digitales Wörterbuch der deutschen Sprache
From Proto-West Germanic *dani.
- ^ Pokorny, Julius (1959) Indogermanisches etymologisches Wörterbuch [Indo-European Etymological Dictionary] (in German), volume 1, Bern, München: Francke Verlag, page 249
From Middle Low German dünne, from Old Saxon thunni, from Proto-West Germanic *þunnī. Cognate with English thin, German dünn.