The Meaning of Senpai
The Japanese word senpai means senior. In informal use, senpai can refer to anyone whose attention you want. Originally this was used hoping a crush or someone they admire will pay attention to them, but it has been used online referring to famous people acknowledging a fan’s existence. Despite what anime and memes would have you believe, senpai is not synonymous with “crush.” In Japan, senpai refers to a more experienced person in any situation.
The Use of Baka
Baka means “crazy,” “foolish,” or “stupid” in Japanese. It can also mean “a fool” or “a stupid person." Anime fans in the West have adopted baka as an insult.