It was no accident, for instance, that Ohio’s leading anti-abortion group, Ohio Right to Life, invoked the term “heartbeat” eight times in 300 words in a news release welcoming the A.C.L.U.’s legal challenge, said the group’s president, Mike Gonidakis. The idea that life begins at conception, an axiom for many anti-abortion activists, Mr. Gonidakis said, does not have the same capacity to mobilize “the average person on the street” as the symbolism of a heart.

“When we say, ‘Protect babies with a beating heart,’ we’ve found a way to overcome that tsunami of messaging from Planned Parenthood,” Mr. Gonidakis said of the prominent abortion rights group. “The power of words and repeating those words over and over again helps steer the debate and move the needle in your favor.”

As abortion opponents push the term “fetal heartbeat,” abortion rights activists are trying to galvanize support by focusing on the impact the recently passed bans can have on people’s lives. On a culture-war battleground where many Americans have already chosen a side, experts say, effective messaging can be the catalyst that mobilizes people on either one — in addition to reaching the undecided.

“‘Heartbeat’ bills are obviously supposed to pull at your heartstrings, and the left is coming back with terms like ‘punishing women’ and ‘forced pregnancy,’” said Mary Ziegler, a legal historian at Florida State University and the author of “After Roe: The Lost History of the Abortion Debate.”

“The rhetoric seems to be getting more and more extreme on both sides,” she added.

Abortion rights advocates say their own polling and analysis has shown that their messaging has been overly focused on concepts like the right to choose and protecting women’s privacy, which were the foundation of 1970s and 1980s-era activism aimed at right-leaning voters opposed to government intervention in people’s lives. Even the term “abortion,” they say, was stigmatized in the late 1990s with the “safe, legal and rare” tagline, used by President Bill Clinton to describe the Democrats’ policy outlook on abortion. Describing abortion as needing to be rare implied incorrectly, in the eyes of advocates, that there was something inherently wrong with having an abortion.