Etymology

Unknown. The word is known to be recent, as the original word for morning in Finnish is huomen. It is likely that once huomen began to be used in words meaning "tomorrow", such as huominen and huomenna, it was eventually replaced by aamu in the sense "morning".
One theory is that aamu is a shortening of the archaic word *huomenhaamu (“morning twilight, morning mist”), which is a compound of huomen (“morning”) + haamu (“twilight, mist, ghost”), but no such compound is attested in older texts, which leaves this theory uncertain. Another theory is that the word is borrowed from the genitive form of Old Swedish *āma (“mist, smoke”) (whence dialectal Swedish åmme), which would have developed the sense "daybreak". While this could be compared to the possible development of aurinko (“sun”) < auer (“haze”), it is likewise uncertain.

Pronunciation

• IPA(key): /ˈɑːmu/, [ˈɑ̝ːmu]
• Rhymes: -ɑːmu
• Syllabification(key): aa‧mu
• Hyphenation(key): aa‧mu

Noun

Period of day

Period of day

aamu

1. morning
   Synonym: (poetic) huomen

Usage notes

As with all words for times of day (except päivä) in Finnish, the adessive case (aamulla) is normally used when talking about events that will take place or took place in the morning. The essive case (aamuna) is used instead, however, if there is a determiner like tämä (“this”), viime (“last”) or ensi (“next”); if the day is specified otherwise, either the essive or adessive case can be used (the former is more common). As usual, other uses, e.g. when postponing events (allative) or with asti (“until”) (illative), may use other locative cases.

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