Romance Languages:
* Spanish: infinito
* French: infini
* Italian: infinito
* Portuguese: infinito
* Romanian: infinit
Germanic Languages:
* German: unendlich
* Dutch: oneindig
* Swedish: oändlig
* Norwegian: uendelig
* Danish: uendelig
* Icelandic: óendanlegur
Slavic Languages:
* Russian: бесконечный (beskonechny)
* Polish: nieskończony
* Czech: nekonečný
* Slovak: nekonečný
* Ukrainian: нескінченний (neskinchenny)
Other Languages:
* Arabic: لانهائي (lā nihā'ī)
* Chinese (Mandarin): 无限 (wúxiàn)
* Japanese: 無限 (mugen)
* Korean: 무한 (muhan)
* Hindi: अनंत (anant)
* Greek: άπειρος (apeiros)
* Latin: infinitus
This is just a small sample of languages. There are many other ways to say "infinite" depending on the language and the context.
Keep in mind that some languages may have multiple words for "infinite" with slightly different nuances.