1) The common admonition ‘look sharp’ requires immediate action from the listener, with no delay allowed.
1785 if you do not look sharp about it ... everything will be void, Meltham.
2) To sharpen.
1424-5 Item Thomć Qwernside pro scharpyng et wellyng of wegges de ferro, Ripon
c.1540 for shoyng oxen and sharpinge the mylne pikks 20d, Esholt
1642 Clippers bringe ... 2 paire of sheares and one or other of them ... a whetstone to sharpe them withall, Elmswell
1708 for sharping masons tooles, Wetherby. In collieries, a blacksmith had to be ‘at Hand’ to sharpen the colliers’ tools, especially their picks and wedges: 1616 picks sharpin 4d, Brandsby
1717 Sam. Bywater for worke sharping 1s 6d, Farnley.