This is the 3879th most frequent Japanese word.
オール
"オール" means "all" or "oar," depending on context.
Here, 'オール' refers to 'oar', a tool for rowing boats.
彼はボートを漕ぐためにオールを使っています。
He is using an oar to row the boat.
In this context, 'オール' is part of 'オールナイト', which means 'all night', referring to spending the entire night doing something.
私たちは昨日オールナイトで遊びました。
We had fun all night yesterday.
Here, 'オール' is used to mean 'overall' or 'entirely', indicating the complete success of the experiment.