No rule for this one
No ending or word group predicts the article of Shampoo. Learn it as a pair and say it out loud: das Shampoo.
Nouns ending in -o only take das 51.9% of the time, so that is not a rule we teach.
das Shampoo
It's das Shampoo. Shampoo is neuter, plural die Shampoos.
Das Shampoo ist im Angebot.
The shampoo is on offer.
No ending or word group predicts the article of Shampoo. Learn it as a pair and say it out loud: das Shampoo.
Nouns ending in -o only take das 51.9% of the time, so that is not a rule we teach.