It is a common belief that dictionary words cannot serve as trademarks. And it is certainty true, but only when a dictionary word is used within its actual original meaning. For example, the word "APPLE" is a generic term for a specific fruit, and so it is impossible to get trademark rights to that word for use with sales of actual apples
However, a common dictionary word can very well be used as an arbitrary and inherently strong trademark if that word is not descriptive of the specific goods for which protection is sought.
Returning to our example, it should be clear now how exactly a certain technology company is able to famously use the word "APPLE" as a trademark in connection with its computers, phones and other digital devices, even though "APPLE" is not a protectable trademark for use in connection with that sweet, edible fruit produced by an apple tree.