2 n. — often in phrase to give someone full marks; figurative, especially Sports
credit given for effort or good performance.
Type: 2. Preservation — The term full marks is often used figuratively mean "all due credit or praise" (see W-3, s.v. "full marks") given for a performance or endeavour, often in sports (see the 1981 quotation) or politics (see the 1978 quotation). Accordingly, OED-3 classifies this sense of full marks as figurative, as there is no numerical mark or score being given. In Canadian English, the figurative sense in the context of sports is more common than meaning 1, and Chart 1 shows that this sense is more common in Canadian English than in other varieties.
See COD-2, s.v. "full marks" (2), which is marked "Cdn & Brit.".
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Chart 1: Internet Domain Search, 5 Oct. 2012