Language matters. What we say can have profound effects on an individual's sense of belonging, self-efficacy, and science identity. One of the ways that these biases can manifest is in our language, through the use of microaggressions. Here, the term "microaggressions" is used to describe brief, sometimes subtle, everyday exchanges that either consciously or unconsciously disparage others based on their personal characteristics or perceived group membership. Microaggressions have moved into the popular lexicon recently, and more people are becoming aware of their existence in both personal and professional contexts. Colleges around the country are increasingly becoming more attentive to microaggressions in the culture of higher education and to the effects of microaggressions on the students and faculty at their institutions. Science can be an isolating and psychologically challenging field for many young scholars who embark upon a scientific career. While some efforts have helped improve the climate for students on some campuses, and strides have been made in increasing access and diversity in science, low retention rates in the sciences and the scarcity of women and people of color in leadership positions show that there is much work to be done in creating a safe and welcoming scientific environment for all.