In this article there is a list of common masculine nouns in Spanish ending in -ma.
Why this list?
Because these words can trip you up ... especially if you are aiming at accuracy in your Spanish.
.....but it is it is up to you whether this level of accuracy is important.
Let's face it - mutual comprehension is the aim of the game when you are learning Spanish. Does it really matter whether you use el or la.
Well, it does and it doesn't.
Are you being understood by the person you are speaking to, or writing to? If this is the case - no hay problema.
If you are sitting a formal exam, of whatever sort, then perhaps it does matter. Well, not even perhaps ... it does matter. Beware the picky examiner (and I have been one!)
Bottom line - it is up to you!
And here is the list in all its glory!
List of common masculine nouns in Spanish ending in -ma
Spanish masculine noun ending in -ma
el coma (la coma = comma)
slogan / watchword
pyjamas (US pajamas)