Periodickým

Periodickým is the instrumental singular masculine and neuter form of the Czech adjective periodický, meaning periodic or occurring at regular intervals. The word is used to describe phenomena, events, or patterns that repeat in a cycle or at fixed intervals, and it appears in both everyday and technical language.

In Czech morphology, periodický declines like other adjectives. The instrumental singular forms are periodickým for masculine and neuter nouns, periodickou for feminine nouns, and periodickými for instrumental plural. For example: Periodickým opakováním se zlepší dovednost (by periodic repetition one improves a skill). In common phrases the adjective also appears in its non-instrumental forms, such as periodické funkce (periodic functions) or periodická tabulka prvků (the periodic table of elements).

Etymology and related forms: periodický derives from the noun perioda with the Czech adjectival suffix -ický, ultimately tracing back to Latin periodicus via historical linguistic development. The root period- is shared with many languages and underpins terms in science and mathematics, such as periodická tabulka prvků and periodické funkce.

See also: the concept of periodicity in science and mathematics, and Czech grammar regarding adjective declension.

Examples of usage across contexts demonstrate the word’s versatility: periodické jevy refer to regularly occurring phenomena, periodická tabulka prvků labels the classic chemistry table, and periodické funkce describe mathematical functions with a fixed period. Overall, periodickým serves as the instrumental form widely used to express “by periodic means” or to describe periodic attributes in Czech.