Hebrew word
matstsâh
mats-tsaw'
מַצָּה
What it means
properly, sweetness
properly, sweetness; concretely, sweet (i.e. not soured or bittered with yeast); specifically, an unfermented cake or loaf, or (elliptically) the festival of Passover (because no leaven was then used)
Where it comes from
from mâtsats (מָצַץ) in the sense of greedily devouring for sweetness