skill
Cross references: 1. art 1. skill \'skil\ n [ME skil, fr. ON, distinction, knowledge; akin to OE scylian to sep]arate, sciell shell - more at SHELL obs 1: CAUSE, REASON 2: the ability to use one's knowledge effectively and readily in execution or performance : technical expertness : PROFICIENCY, DEXTERITY 3: a learned power of doing a thing competently : a developed aptitude or ability 2. skill vi archaic : to make a difference : MATTER, AVAIL