Something that is needless is completely unnecessary.
例句
But his death was so needless...但他的死太沒有必要了。'I have never knowingly exposed any patient to needless risks,' he said.他說：“我從未故意將任何病人置于不必要的風險境地。”
PHRASE
不用說;不必說
You use needless to say when you want to emphasize that what you are about to say is obvious and to be expected in the circumstances.
例句
Our budgie got out of its cage while our cat was in the room. Needless to say, the cat moved quicker than me and caught it.我們的虎皮鸚鵡飛出鳥籠的時候，貓正好在室內。不用說，貓比我快，抓住了它。
英漢詞典釋義
adj.
不需要的;不必要的
It is needless to add that you are in want of a second.你需要一個助手,那是不必說的。
當然；不用說
Needless to say, the students who had studied mathematics before did better in the statistics exam.不用說，以前學過數(shù)學的學生統(tǒng)計學考得比較好。He got home from the party the next morning. Needless to say, his parents were furious.他參加聚會第二天早晨才回家，不用說，他的父母大發(fā)雷霆。
英英詞典釋義
Adjective
1. unnecessary and unwarranted;
"a strikers' tent camp...was burned with needless loss of life"