Ireland’s prime minister, Leo Varadkar, conceded defeat Saturday as two constitutional amendments he supported that would have broadened the definition of family and removed language about a woman’s role in the home were headed toward rejection.

Mr. Varadkar, who pushed the vote to enshrine gender equality in the constitution by removing “very old-fashioned language” and tried to recognize the realities of modern family life, said that voters had delivered “two wallops” to the government.

“Clearly we got it wrong,” he said. “While the old adage is that success has many fathers and failure is an orphan, I think when you lose by this kind of margin, there are a lot of people who got this wrong and I am certainly one of them.”

Opponents argued that the amendments were poorly worded, and voters said they were confused with the choices that some feared would lead to unintended consequences.

The proposal to alter wording in the constitution to include families which are not based on marriage was defeated with 67.7% voting ‘no’. A second proposed change on the wording around the role of women in the home was defeated by a higher margin, with 73.9% of voters rejecting it. It was the highest ever no vote percentage in an Irish referendum.

The referendum was viewed as part of Ireland’s evolution from a conservative, overwhelmingly Roman Catholic country in which divorce and abortion were illegal, to an increasingly diverse and socially liberal society. The proportion of residents who are Catholic fell from 94.9 percent in 1961 to 69 percent in 2022, according to the Central Statistics Office.

The social transformation has been reflected in a series of changes to the Irish Constitution, which dates from 1937, though the country wasn’t formally known as the Republic of Ireland until 1949. Irish voters legalized divorce in a 1995 referendum, backed same-sex marriage in a 2015 vote and repealed a ban on abortions in 2018.

The first question dealt with a part of the constitution that pledges to protect the family as the primary unit of society. Voters were asked to remove a reference to marriage as the basis “on which the family is founded” and replace it with a clause that said families can be founded “on marriage or on other durable relationships.” If passed, it would have been the constitution’s 39th amendment.

A proposed 40th amendment would have removed a reference that a woman’s place in the home offered a common good that couldn’t be provided by the state, and delete a statement that said mothers shouldn’t be obligated to work out of economic necessity if it would neglect their duties at home. It would have added a clause saying the state will strive to support “the provision of care by members of a family to one another.”

Siobhán Mullally, a law professor and director of the Irish Center for Human Rights at the University of Galway, said that it was patronizing for Mr. Varadkar to schedule the vote on International Women’s Day thinking people would use the occasion to strike the language about women in the home. The so-called care amendment wasn’t that simple.

While voters support removing the outdated notion of a woman’s place in the home, they also wanted new language recognizing state support of family care provided by those who aren’t kin, she said. Some disability rights and social justice advocates opposed the measure because it was too restrictive in that regard.

“It was a hugely missed opportunity,” Ms. Mullally said. “Most people certainly want that sexist language removed from the constitution. There’s been calls for that for years and it’s taken so long to have a referendum on it. But they proposed replacing it with this very limited, weak provision on care.”

Mr. Varadkar said that his camp hadn’t convinced people of the need for the vote — never mind issues over how the questions were worded. Supporters of the amendment and opponents said the government had failed to explain why change was necessary or mount a robust campaign.

“The government misjudged the mood of the electorate and put before them proposals which they didn’t explain and proposals which could have serious consequences,” Senator Michael McDowell, an independent who opposed both measures, told Irish broadcaster RTE.

Labour Party Leader Ivana Bacik told RTE that she supported the measures, despite concerns over their wording, but said the government had run a lackluster campaign.

The debate was less charged than the arguments over abortion and gay marriage. Ireland’s main political parties all supported the changes, including centrist government coalition partners Fianna Fail and Fine Gael and the biggest opposition party, Sinn Fein.

One political party that called for “no” votes was Aontú, a traditionalist group that split from Sinn Fein over the larger party’s backing for legal abortion. Aontú leader Peadar Tóibín said that the government’s wording was so vague that it would have led to legal wrangles and most people “do not know what the meaning of a durable relationship is.”

Opinion polls had suggested support for the “yes” side on both votes, but many voters on Friday said they found the issue too confusing or complex to change the constitution.

“It was too rushed,” said Una Ui Dhuinn, a nurse in Dublin. “We didn’t get enough time to think about it and read up on it. So I felt, to be on the safe side, ‘no, no’ — no change.”

Caoimhe Doyle, a doctoral student, said that she voted yes to changing the definition of family, but no to the care amendment because “I don’t think it was explained very well.”

“There’s a worry there that they’re removing the burden on the state to take care of families,” she said.