obviously; needless to say; it goes without saying
Used to introduce a statement that is obvious or universally accepted. Often appears at the beginning of a sentence or clause.
言うまでもなく、健康は大切だ。
Needless to say, health is important.
言うまでもなく、彼はその仕事に最適な人材だ。
Obviously, he is the best person for the job.
当然 means 'naturally' or 'as a matter of course', focusing on logical expectation, while 言うまでもなく stresses that something is so obvious it need not be said.
言うまでもなく means 'needless to say' and stands alone, while ましてや connects two clauses to show that a claim applies even more strongly to a second case.
Standard kanji-kana mixed spelling.
Variant using the kanji 無 for なく.
Rare variant using 迄 for まで.
Rare variant combining 迄 and 無.
From the phrase 言う (to say) + までも (even until) + なく (without), literally 'without even needing to say'. The expression became fixed as an adverbial phrase meaning 'obviously' or 'needless to say'.