There are over 300 nouns in German that end with “ant”, and almost all of them are masculine (i.e. they have the article “der”), such as:
der Elefant (elephant)
der Gigant (giant)
der Hydrant (hydrant)
der Praktikant (intern, trainee)
There are only four commonly used nouns ending with -ant that are not masculine (they are all neuter):
das Croissant (croissant)
das Deodorant (deodorant)
das Restaurant (restaurant)
Note that “Croissant” and “Restaurant” are pronounced the same way as in French, with a nasal /sɑ̃/ at the end (or, less commonly, /saŋ/, “sahng”). The only other nouns (which are all rather uncommon) breaking the pattern are:
das Dispersant (dispersant, a dispersing agent added to a suspension)
das Reaktant (reactant, a substance consumed during a chemical reaction)
The word Volant (ruffle, frill; in Austrian German also a dated expression for a steering wheel) may be either masculine or neuter.
For completeness, we should mention that the rule may be applied also to monosyllabic nouns (where -ant is not a suffix), e.g. der Fant (young, inexperienced person), der Grant (feeling of resentment; only used in Bavaria and Austria), der Spant (also das Spant; a frame of a ship or an aircraft), with just a single exception of die Want (shroud, a rope supporting a mast on a ship).