A massive object is, at its etymological core, a lump of bread dough. The word arrives from Middle French massif, from Old French masse, from Latin massa — 'kneaded dough, a lump'. The Latin itself comes from Greek maza, a barley cake, from the verb massein meaning 'to knead'.
The Proto-Indo-European root *maḱ- meant 'to knead' or 'to press', and from this kitchen action grew a word family spanning physics, geography, and confectionery. Mass in the scientific sense — the quantity of matter in a body — traces directly back to the idea of a shapeable lump.
The French massif survives in English as a geographical term: a mountain massif is a compact group of peaks, literally a solid mass of rock. The Central Massif of France carries the word in its purest sense.
Marzipan belongs to this family too, arriving through Arabic from the same Latin massa. Massacre has a grimmer connection: it originally meant a butcher's shambles — a mass of flesh on the block.
In modern usage, massive has drifted far from dough. It describes stars, debts, and earthquakes. But the original image — hands pressing and shaping a heavy lump — remains buried in the word.