In recent weeks, the phrase "ok, boomer" has been trending on social media as a clap-back at those expressing opinions deemed outdated or out of touch. "Boomer" references the baby boom generation, usually defined as those born between 1946 and 1964. As now used, however, the phrase "ok, boomer" is not always directed exclusively at baby boomers, and even a teenager could find herself on the receiving end of a snarky "ok, boomer."

As the phrase rises in popularity, some boomers have complained that it is ageist, akin to a slur against those in their mid-fifties through mid-seventies. Meanwhile, users of the phrase may not consider it to be ageist at all or, if they do, see little harm in "punching up" against a generation perceived as unduly advantaged.

From perhaps the boomeriest perspective on this debate—that of employment law—the phrase is probably better left on social media and out of the workplace. The federal Age Discrimination in Employment Act (ADEA), passed by Congress in 1967, prohibits discrimination against workers aged 40 and over.

Whether remarks are considered discriminatory does not depend on the intent of the speaker, but instead on the understanding of the recipient, so long as that understanding is objectively reasonable. In the context of "ok, boomer" then, it really doesn't matter whether the phrase is or is not ageist in some absolute sense. The fact that older workers might reasonably construe the phrase as ageist could be sufficient to support an age discrimination claim. In the case of similar legally-protected characteristics, such as sex or race, it is fairly obvious that phrases that might reasonably be construed as demeaning someone on the basis of such characteristics (a dismissive "ok, girl" or "ok, boy" for example) should be avoided at work.

Age discrimination may feel different, in no small part because companies frequently are run by managers over the age of 40, with younger workers occupying lower rungs on the organizational hierarchy. But, in Congress' judgment, workers over 40 are (for the most part) protected to the same extent against discrimination as are employees on the basis of sex or race. Nor does it matter that younger workers might also shoot an "ok, boomer" at one another from time to time. The term "geezer" could be directed at anyone, but courts have recognized that its use in the workplace could support an age discrimination claim by an over-40 worker.

While the phrase "ok, boomer" might support a claim of age discrimination, it is critical to note it would be only one building block to such a claim. Occasional use of the phrase in the workplace is not itself sufficient to prevail under the ADEA. To make out a prima facie claim of age discrimination under the ADEA, an employee must prove, among other things, that he or she suffered an adverse employment action, such as a demotion, suspension, cut in pay, or dismissal. If the employee makes out a prima facie case, and the employer responds with a legitimate reason for the adverse action, then the burden shifts back to the employee to prove that the employer's stated reason was really a pretext for age discrimination. It is at this stage in the analysis that evidence of age-based animus would become important. So if, for example, a supervisor directed "ok, boomer" at an ADEA-protected employee and soon after took an adverse action against the employee, the employee could cite the phrase as evidence that the adverse action was in fact the result of age-based animus.

Absent an adverse employment action, a 40-plus employee could still prove a violation of the ADEA by means of a "hostile work environment" theory. Sporadic use of an arguably ageist put-down such as "ok, boomer" by co-workers or even supervisors would not be enough. Instead, the age-based harassment must be sufficiently severe or pervasive to alter the employee's conditions of employment and create an abusive atmosphere.

Notwithstanding the above legal hurdles, a total of 16,911 complaints of age discrimination were filed with the EEOC last year alone. Many more claims were filed under state laws, some of which will permit a finding of discrimination even in the absence of severe or pervasive conduct. Precisely because most users of the phrase "ok, boomer" would not consider it comparable to verbal slights related to other legally-protected characteristics, its use in the workplace has the potential to increase that number of annual age discrimination complaints, most notably when used by supervisors and directed at subordinates age 40 or over.

Joseph P. Sirbak II is a member of Cozen O'Connor in Philadelphia. He focuses his practice on labor and employment matters.