Information from this page can found in "Cornell LGBTQ+ Resource Guide for Faculty and Staff", from Cornell University.
(Micro)aggressions are the everyday verbal, nonverbal, and environmental slights, snubs, or insults — whether intentional or unintentional --that communicate hostile, derogatory, or negative messages and target persons based solely upon their marginalized group membership.
As a faculty member, you are in a position of power to create classroom norms that counteract such (micro) aggressions and assert they are unacceptable in your classroom.