An acrobat is someone who skillfully performs gymnastic feats or other actions that involve agility and balance, such as a trapeze artist soaring through the air, or a tightrope walker at the circus.
You may be tempted to conclude that the bat in acrobat is a tribute to the animal that soars through the air when not hanging upside down. The source is not quite that creative. It comes from bainein, which is Greek for "to walk." The acro bit comes from akros, meaning "highest point." So acrobat is a reference to the classic and possibly first trick perfected by these artists, tightrope walking.