A relief aircrew member, often used on long-distance flights.

Alternative form of easy as falling off a log

Improper, immoral behavior / Irritating or self-indulgent behavior

(neologism, derogatory) The Republican Party of the United States.

(idiomatic) Especially; more than other things. / (idiomatic, often used as a sentence adverb) Surprisingly.

(anatomy) A circle of arteries at the base of the brain that is formed by the cerebral and communicating arteries and is a site of aneurysms.

Alternative form of put one over

(idiomatic) To focus excessively on one's plans or on prospective future events without paying adequate attention to the present.

(obsolete) Algebra.

(idiomatic) To be knowledgeable about, and competent at, a particular subject or task.