autumn; CL:個|个[ge4]
秋 · 9 strokes
Originally a pictograph of a cricket, since cricket chirps indicate the beginning of autumn. Later the character was reanalyzed as 禾 (grain) + 火 (fire).
天 · 4 strokes
Depicts a person (大) with an emphasized head. Based on the original meaning "head". The meaning later shifted to "top", "high", and "sky".