Look up this word
customer

In a sentence
Tom je dobrý zákazník.
Tom is a good customer.
Má zákazník vždy pravdu?
Is the customer always right?
Zákazník má vždy pravdu.
The customer is always right.
V tomto obchode nevidím ani jedného zákazníka.
I don't see a single customer in this store.
Examples from Tatoeba (CC BY 2.0 FR).
Source
Slovak National Corpus (SNK) ↗English gloss from the frequency publish path. Includes Tatoeba example sentences when present.
Full attribution on References.