thematic
the.mat.ic \thi-'mat-ik\ \-i-k(*-)le-\ aj [Gk thematikos, fr. themat-, thema theme] 1a: of or relating to the stem of a word of a vowel 1b: being the last part of a word stem before an inflectional ending 2: of, relating to, or constituting a theme - the.mat.i.cal.ly av