Microorganism
Microbe
noun
A delicate life thing (生物 = biology) is a life thing that is very delicate. So small and delicate. It's a microorganism.
びせいぶつ
This is a jukugo word, which usually means on'yomi readings from the kanji. If you know the readings of your kanji you'll know how to read this as well.
微生物学の専門家は何時に来る予定ですか。
What time is the microbiology specialist scheduled for?