dis·ser·tate 
(dĭsər-tāt′) also dis·sert (dĭ-sûrt)
(dĭsər-tāt′) also dis·sert (dĭ-sûrt)intr.v. dis·ser·tat·ed, dis·ser·tat·ing, dis·ser·tates also dis·sert·ed or dis·sert·ing or dis·serts
1. To discourse formally.
2. To prepare a dissertation.
[Latin dissertāre, dissertāt-, frequentative of disserere, to discuss : dis-, dis- + serere, to connect; see ser-2 in the Appendix of Indo-European roots.]
disser·ta′tor n.