Spick and span means entirely new - fresh or unused. What is unclear is the origin of the phrase. It can be traced back as far as Sir Thomas North's translation of Plutarch's Lives of the noble Grecians and Romanes, 1579:
"They were all in goodly gilt armours, and brave purple cassocks apon them, spicke, and spanne newe."By the 1660s spicke and spanne-newe had turned into spicke and span and appears in Samuel Pepys' Diary, 1665:
"My Lady Batten walking through the dirty lane with new spicke and span white shoes."My usual source of word origins is the Oxford English Dictionary but it has a dubious origin for this phrase and says the old Dutch word spikspeldernieuw refers to newly made ships. It suggests that this is the origin of spick but offers no reason for that belief and none of the early citations of the phrase refer to shipping.
In fact the noun spick had many different meanings including a side of bacon, a floret of lavender, a nail or spike, and a thatching spar. Similarly, span had several meanings, including: the distance from the tip of the thumb to the tip of the little finger, a measure of butter, a fetter or chain, and a chip of wood. As a result all sorts of combinations are possible but at the end of the day the derivation of the term isn't clear and the best efforts to explain it so far are little more than informed guesses.