What does Boxing Day have to do with boxing?
"having a sharp slope," Old English steap "high, lofty," from Proto-Germanic *staupaz (cf. Old Frisian stap, Middle High German *stouf), from PIE *steup- "to push, stick, knock, beat," with derivations referring to projecting objects (cf. Greek typtein "to strike," typos "a blow, mold, die;" Sanskrit tup- "harm," tundate "pushes, stabs;" Gothic stautan "push;" Old Norse stuttr "short"). The sense of "precipitous" is from c.1200. The slang sense "at a high price" is a U.S. coinage first attested 1856. Related: Steeply; steepness.
"to soak in a liquid," late 14c., of uncertain origin, originally in reference to barley or malt, probably cognate with Old Norse steypa "to pour out, throw" (or an unrecorded Old English cognate), from Proto-Germanic *staupijanan. Related: Steeped; steeping.
He or she was or is very angry: Houk was red-faced with anger. Steam was coming out of his ears (1960s+)