1. (

• acute ,
• discriminating ,
• incisive ,
• keen ,
• knifelike ,
• penetrating ,
• penetrative ,
• piercing ,
• sharp

) having or demonstrating ability to recognize or draw fine distinctions; "an acute observer of politics and politicians"; "incisive comments"; "icy knifelike reasoning"; "as sharp and incisive as the stroke of a fang"; "penetrating insight"; "frequent penetrative observations" ;

2. (

• incisive

) suitable for cutting or piercing; "incisive teeth" ;