Brown-Driver-Briggs (BDB)
H4682
H4682 מַצָּה unleavened bread , or cake(s)
Brown-Driver-Briggs Hebrew Lexicon (BDB), 1906 — public domain
Strong's H4682 · Hebrew
mats-tsaw'
from 4711 in the sense of greedily devouring for 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)
Brown-Driver-Briggs (BDB)
Brown-Driver-Briggs Hebrew Lexicon (BDB), 1906 — public domain