Answer:

thematic

Answer	Crossword Clue
THEMATIC	On topic
THEMATIC	Topical
THEMATIC	Pertaining to the principal subject.

THEMATIC	Of a musical motif.
THEMATIC	Topical.
THEMATIC	Of a motif
THEMATIC	Like an apperception test
THEMATIC	Dealing with a subject
THEMATIC	Pertaining to the subject
THEMATIC	Like some passages in a symphony
THEMATIC	Related to motifs

THEMATIC	With common elements