pre·oc·cu·pied 
(prē-ŏkyə-pīd′)
(prē-ŏkyə-pīd′)adj.
1.
a. Absorbed in thought; engrossed.
b. Excessively concerned with something; distracted.
2. Formerly or already occupied.
3. Already used and therefore unavailable for further use. Used of taxonomic names.