This is the 12565th most frequent Russian word.
комплексах
"Комплексах" is the prepositional plural form of "комплекс," meaning "complexes" (e.g., sets of interconnected things or psychological complexes).
Here, 'комплексах' is used as a plural locative form of the noun 'комплекс', referring to sports facilities or centers.
Он работает в спортивных комплексах.
He works in sports complexes.
In this sentence, 'комплексах' refers to psychological complexes or insecurities that a person might experience.
Она рассказывала о своих комплексах.
She was talking about her insecurities.
In this context, 'комплексах' refers to biological systems or structures, used metaphorically or in scientific terminology.