"Scots Gaelic"
"the Scots community in New York"
"`Scottish' tends to be the more formal term as in `The Scottish Symphony' or `Scottish authors' or `Scottish mountains'"
"`Scotch' is in disfavor with Scottish people and is used primarily outside Scotland except in such frozen phrases as `Scotch broth' or `Scotch whiskey' or `Scotch plaid'"

"an economical meal"
"an economical shopper"
"a frugal farmer"
"a frugal lunch"
"a sparing father and a spending son"
"sparing in their use of heat and light"
"stinting in bestowing gifts"
"thrifty because they remember the great Depression"
"`scotch' is used only informally"

"What ultimately frustrated every challenger was Ruth's amazing September surge"
"foil your opponent"