allakäikudest

Could you clarify what you mean by "allakäikudest"? In Estonian, the term could have several possible senses, and I want to ensure I write the article in the intended context. Options include:

- A grammatical or linguistic sense (for example, a word-form or case-related usage involving "allakäik" in Estonian grammar)

- An architectural or urban-planning sense (for instance, referring to lower-level passages, corridors, or stair-related structures)

- A cultural, historical, or place-name sense (such as a specific concept, tradition, or location associated with the term)

Once you specify the intended sense and the target audience (general audience, academic, etc.), I will provide a concise, neutral wiki-style article under 300 words.