The older English word behind pretty concerned craftiness or tricks. Later uses moved toward cleverness, pleasing workmanship, and attractive appearance. The dictionary evidence supports the early meaning even though the precise transition between some historical forms has gaps.
The early sense is the scored claim. The detailed continuity between Old and Middle English forms has uncertainties.
Sources
- Merriam-Webster · pretty
The word’s etymology and recorded senses.
- Etymonline · pretty
Additional context for the meaning or borrowing history.