spar (n.1) Look up spar at Dictionary.com
early 14c., "rafter;" late 14c., "stout pole," from or cognate with Middle Low German or Middle Dutch sparre, from Proto-Germanic *sparron (cognates: Old English *spere "spear, lance," Old Norse sperra "rafter, beam," German Sparren "spar, rafter"), from PIE root *sper- (1) "spear, pole" (see spear (n.1)). Nautical use, in reference to one used as a mast, yard, boom, etc., dates from 1630s. Also borrowed in Old French as esparre, which might be the direct source of the English word.
spar (v) Look up spar at Dictionary.com
late 14c., "go quickly, rush, dart, spring;" c.1400, "to strike or thrust," perhaps from Middle French esparer "to kick" (Modern French éparer), from Italian sparare "to fling," from Latin ex- (see ex-) + parare "make ready, prepare," hence "ward off, parry" (see pare). Etymologists consider a connection with spur unlikely. Used in 17c. in reference to preliminary actions in a cock fight; figurative sense of "to dispute, bandy with words" is from 1690s. Extension to humans, in a literal sense, with meaning "to engage in or practice boxing" is attested from 1755. Related: Sparred; sparring.
spar (n.2) Look up spar at Dictionary.com
"crystalline mineral that breaks easily into fragments with smooth surfaces," 1580s, from Low German Spar, from Middle Low German *spar, *sper, cognate with Old English spær- in spærstan "gypsum."