That's an oversight. It's <ú>, which is just /uː/. Within Lilitika's tense-lax system, /uː iː eː/ <ú í é> are paired with /ʌ ɪ ɛ/ <u i e>. Usually the accent of a word has to fall on a tense vowel, with the unpaired /oː/ <o> also counting as tense and the unpaired /a/ <a> counting as lax. Designating where stress falls in a word—especially if it happens to be on a short vowel, as is the case in certain verb forms of the Illeran dialect—got to be such a headache that I developed a Greek "Hellenic" transliteration that still required numerous digraphs even after adding in several Coptic letters.

The three other vowels (/ɒ yː ɔː/ <ô ê û>) are used almost exclusively in interjections and a few modern loanwords, although <ê> does appear in a few roots: <bosêt-> (/boːsyːt/), "luxury," and <vêdt->  (/vyːɾ/ or /vøːɾ/), "precision." It might be a fossilized imitation of a prestigious sociolect.