1. 暴发户：upstandstring 上翻边梁 | upstart 暴发户 | upstation 上端局

2. 自命不凡的人：upside down 颠倒 | upstart 自命不凡的人 | uptake 摄取

3. 突然升官的人,暴发户：524. understudy: 预备演员,替角. V. | 525. upstart: 突然升官的人,暴发户. | 526. urchin: 顽童.

4. 爆富：ups and downs 盛衰 | upstart 爆富 | vanish to thin air 消失的无影无踪

1. （初到某地或初出茅庐却）自命不凡的家伙
You can refer to someone as an upstart when they behave as if they are important, but you think that they are too new in a place or job to be treated as important.

e.g. Many prefer a familiar authority figure to a young upstart.
很多人都更愿意跟自己熟悉的权威人物打交道，而不是一个年纪轻轻却自命不凡的家伙。
e.g. ...an upstart who had come from nowhere.
原本是个无名之辈的目中无人的新丁

noun

1. a gymnastic exercise performed starting from a position with the legs over the upper body and moving to an erect position by arching the back and swinging the legs out and down while forcing the chest upright

Synonym: kip

2. a person who has suddenly risen to a higher economic status but has not gained social acceptance of others in that class

Synonym: parvenunouveau-richearriviste

3. an arrogant or presumptuous person