Gerund: the act or process of chewing.
Proper masticating is essential for good digestion.
Une bonne mastication est essentielle à une bonne digestion.
masticatinggerund / present participle Used adjectivally as the present participle of "masticate".
The masticating insects caused severe damage to the leaves.
Les insectes masticants ont causé de graves dégâts aux feuilles.