one mountain
Literal counting of a single mountain. Often used in contexts like hiking or geography.
Today I walked over one mountain to the next village.
Refers to a pile or heap of items, or a batch/lot in sales or auctions. Often used with counters or in commercial contexts.
I bought a pile of vegetables at the market for a set price.
I won a whole lot at the auction.
hump; worst part
Metaphorical use: the peak or hardest part of a task, or a hump-shaped obstacle. Often in phrases like 一山越える (get over the hump).
Once we get over the hump of this project, the rest will be easy.
large profit; killing
Used in the set phrase 一山当てる (to make a killing, strike it rich). Not used independently for profit.
See also: 一山当てる (ひとやまあてる)
He made a killing in stocks.
dirt cheap; very cheap; worthless · lot (in a sale); bulk purchase unit
Standard kanji spelling; high frequency in news.
Mixed kana-kanji spelling, common in everyday writing.
Compound of 一 (one) and 山 (mountain). The extended meanings (pile, hump, profit) derive from the image of a single mountain-like heap or obstacle.