チョウ, きざ.す, きざ.し
portent, 10**12, trillion, sign, omen, symptoms
JLPT2 G4 S6 F1174
A depiction of animal bones and tortoise shells baked in divination rites, showing the curving cracks/splits that were scrutinized in *fortunetelling* → *sign*; *indication*; *omen* → *symptom*. *Trillion* is a borrowed meaning.
[Full Kanji Etymology List]