The word 'withal' is a fossilized compound from Middle English, originating from the combination of the preposition 'with' and the adverb 'all'. Its formation is analogous to other archaic adverbs like 'therewithal'. The preposition 'with' itself has Germanic roots, deriving from Old English 'wiþ', meaning 'against, opposite, toward', which evolved to signify association or accompaniment. Over time, 'withal' condensed from the phrase 'with all' into a single adverb meaning 'in addition' or a preposition meaning 'with', often used for emphasis or to conclude a statement, preserving a formal and somewhat archaic tone in modern English.

This is a Middle English compound formed from the preposition 'with' and the archaic adverb 'all'. It is a tight Germanic formation where the components have fused into a single lexical unit.