Meaning of QUANTUM in English
[quan.tum] n, pl quan.ta [L, neut. of quantus how much] (1567) 1 a: quantity, amount b: portion, part c: gross quantity: bulk
2. a: any of the very small increments or parcels into which many forms of energy are subdivided b: any of the small subdivisions of a quantized physical magnitude (as magnetic moment)
quantum adj (1942): large, significant "a ~ improvement"
Merriam-Webster English vocab. Английский словарь Merriam Webster. 2012