What is the X in X-mas?
"person or animal that hops," mid-13c., agent noun from hop (v.). From c.1200 as a surname, and perhaps existing in Old English (cf. hoppestre "female dancer").
"container with narrow opening at bottom," late 13c., perhaps an agent noun from hop (v.) via notion of grain juggling in a mill hopper.
American mathematician and computer programmer who in 1951 conceived the idea for an internal computer program, called a compiler, that scanned a set of alphanumeric instructions (such as words and symbols) and compiled a set of binary instructions executed by the machine. Her ideas were widely influential in the development of programming languages, in particular COBOL.
A ground ball that hops along (1940s+ Baseball)