Implies a superficial understanding of someone's personality or demeanor that could change. On first acquaintance, she seemed reserved, but she's quite outgoing.
Pro Tip 2/3
Cultural Nuance
Often used to describe the initial meeting within a specific cultural or social context. On first acquaintance, his etiquette reflected a distinct British formality.
Pro Tip 3/3
Misleading Firsts
Can be used to express the idea that initial judgments may not be accurate. On first acquaintance, his humor went unnoticed.