Pronunciation: [sˈʌbtəlˌa͡ɪzd] (IPA) 
The spelling of the word "subtilised" is intriguing. It is pronounced /sʌbtɪlaɪzd/, with the stress on the second syllable. The use of the "t" between "l" and "i" seems odd. However, this spelling follows the British English convention for adding "-ize" to words that have a "t" already, such as "subtle." In American English, the spelling would be "subtilized." Either way, the word means to make something more subtle or refined.
The word "subtilised" is derived from the word "subtle".
"Subtle" comes from the Latin word "subtilis", which means "fine, delicate, or thin". It evolved from the combination of the prefix "sub" (meaning "under" or "below") and "tela" (meaning "web" or "fabric"). In Latin, the word "subtilis" was used to describe something that was finely woven or made up of thin threads.
Over time, the meaning of "subtle" expanded to describe things that were not easily noticeable or understood. It came to denote something refined, delicate, or nuanced. "Subtilised" is the past tense form of "subtilise", which means to make something subtle or refine it in a delicate manner.
