The Reserve Bank of Australia may want to use SpellCheck.

An eagle-eyed observer spotted an embarrassing typo — “responsibility” misspelled as “responsibilty” — in about 46 million of the “new and improved” $50 bills.

The banknotes, which were rolled out in October amid much fanfare about their anti-counterfeiting measures, feature Edith Cowan, the first female member of an Australian parliament.

What looks like a lawn in the background of her portrait is actually rows of text — a quotation from her first speech to parliament.

“It is a great responsibilty [sic] to be the only woman here, and I want to emphasise the necessity which exists for other women being here” is repeated several times in microscopic print.

About 400 million new notes — which also include the image of writer and inventor David Unaipon and excerpts from his book, “Legendary Tales of the Australian Aborigines” — were printed.

Roughly 46 million of them are now in circulation with a total value of around $2.3 billion.

The RBA confirmed the typo Thursday and said the error would be corrected in future print runs, according to The Australian.

The $50 bill, worth $34.90 in US currency, contains anti-counterfeiting measures including a flying swan and a holographic 50 that reverses when the note is moved.

“These banknotes are legal tender and can continue to be used as normal. It does not affect their validity and functionality in any way,” an RBA spokeswoman told CNN about the bills with the typos.

“We have reviewed our processes to remove the likelihood of such an error occurring in the future.”