die Masse
mass / crowd
A large, indefinite number of people or things.
Eine riesige Masse an Menschen wartete vor dem Stadion.
A huge crowd of people was waiting in front of the stadium.

mass / crowd
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mass / crowd
A large, indefinite number of people or things.
Eine riesige Masse an Menschen wartete vor dem Stadion.
A huge crowd of people was waiting in front of the stadium.

To express a large quantity of something, the structure 'eine Masse an' + noun in the dative plural is often used. This emphasizes the large, unmanageable number.
Wir mussten eine Masse an neuen Informationen verarbeiten.
We had to process a mass of new information.
The idiom 'aus der Masse herausstechen' means to stand out positively from others through special qualities or achievements.
Mit ihrem kreativen Projekt stach sie deutlich aus der Masse heraus.
With her creative project, she clearly stood out from the crowd.
The meaning 'formless substance' is often found in recipes or construction instructions. Typical verbs are 'verrühren' (to stir together), 'kneten' (to knead), or 'mischen' (to mix), and adjectives are 'glatt' (smooth), 'zäh' (sticky/tough), or 'fest' (firm).
Rühren Sie das Mehl und die Eier zu einer glatten Masse.
Stir the flour and eggs into a smooth mass.
The expression 'die breite Masse' (the general public) is a fixed phrase and refers to the largest part of the population, meaning average citizens.
Der neue Superheldenfilm soll vor allem die breite Masse ansprechen.
The new superhero film is meant to appeal above all to the general public.
In physics, 'Masse' (mass) is an exact technical term. You can recognize this meaning from words like 'Kilogramm' (kilogram), 'Gewicht' (weight), or 'Gravitation' (gravitation) in the context of the natural sciences.
Die Anziehungskraft zwischen zwei Körpern hängt von ihrer Masse ab.
The gravitational attraction between two objects depends on their mass.
million
'Millionen' and 'die Masse' can both refer to a very large amount. 'Millionen' suggests an extremely large number and, in the plural, is often also used in an exaggerated or imprecise way. 'die Masse' generally means a large, indefinite number of people or things. It is not about an exact number. If you want to strongly emphasize the size, 'Millionen' works well. If you simply mean a large amount as a whole, 'die Masse' is more natural.

Nach dem Konzert ging die Masse langsam Richtung Ausgang.
After the concert, the crowd slowly headed toward the exit.
Im Internet gibt es Millionen von Rezepten für einfache Gerichte.
There are millions of recipes for simple dishes on the internet.