Answer:

TWEEDY

Answer	Crossword Clue
TWEEDY	Wilco frontman Jeff
TWEEDY	Like Jane Marple's wardrobe
TWEEDY	Collegiately dressed

TWEEDY	Academically stylish
TWEEDY	Made of rough wool fabric
TWEEDY	Like a casual suit
TWEEDY	Like Miss Marple's attire
TWEEDY	Casually attired
TWEEDY	Miss Marple-esque
TWEEDY	Like some professors' wardrobes
TWEEDY	Very English, as to suits.

TWEEDY	Describing a well-dressed sportsman.
TWEEDY	Descriptive of a type of dress.
TWEEDY	Of a certain weave, as suits.
TWEEDY	Like certain fabrics.
TWEEDY	Like some Britishers.
TWEEDY	Like an outdoorsy Englishman
TWEEDY	Outdoorsy
TWEEDY	Outdoorsy in taste or habits

TWEEDY	Informal in taste
TWEEDY	Like some professors' suits
TWEEDY	Like some professorial attire
TWEEDY	Academic style