The word "littleused" is spelled with a double "t" after the "e" because it follows the rule for doubling consonants after a short vowel sound. The IPA phonetic transcription for "littleused" is /ˈlɪtəljuːzd/. The "i" sound in the first syllable is a short vowel sound, making the "t" doubled in the second syllable. The "u" in the second syllable is pronounced like "oo". "Littleused" means something that is rarely used or hardly used at all.
The word "littleused" is not commonly found in dictionaries or language resources, suggesting that it is not a recognized word in English. It may be a combination of the two words "little" and "used" to imply something that is not extensively used or that has seen limited use.