The perceptions and definitions of tomboy behavior were explored across three generations of women. The sample included 521 women (primarily undergraduates, their mothers, and their grandmothers) ranging in age from 17 to 94 who were categorized into one of three cohorts (Generation Xers, Baby Boomers or Senior Citizens) for a final sample of 466. The sample was 87% European American, 6% Native American, 3% Hispanic, and 2% Asian American. Sixty-seven percent of the sample reported being tomboys during their childhood. The average age reported for starting tomboy behavior was 5.8, whereas the average age for ceasing tomboy behavior was 12.6. Age cohort analyses revealed relatively few differences but several interesting findings. The senior citizens tended to differ from both sets of younger women. For instance, senior citizens were less likely to report being tomboys than were Xers or Boomers. Directions for future research include monitoring the social acceptability of tomboy behavior, assessing potential cultural differences in tomboyism, and analyzing correlates of the average age that tomboyism ceases.