Answer:

habit

Answer	Crossword Clue
HABIT	Fingernail chewing, for one
HABIT	Way of life
HABIT	It should be kicked if it's bad

HABIT	Addiction
HABIT	Smoking, for one
HABIT	Garb
HABIT	Second nature
HABIT	Behavioral rut
HABIT	Custom
HABIT	Sister's dress
HABIT	Horseback attire

HABIT	What's on a nun
HABIT	Equestrian garb
HABIT	Thing sometimes kicked
HABIT	It may be kicked
HABIT	Unshakable behavior pattern
HABIT	Tough thing to break
HABIT	It can be a good thing to break
HABIT	Sister's attire

HABIT	Nun's apparel
HABIT	Nail-biting, e.g.
HABIT	It's tough to break one
HABIT	Nun's attire
HABIT	Dominant tendency
HABIT	"Breaking the ..": 2004 Linkin Park hit
HABIT	Hard thing to kick
HABIT	Good thing to kick

HABIT	Order clothes
HABIT	Sister's outfit
HABIT	Convent outfit
HABIT	Nun's wear
HABIT	Target of a New Year's resolution
HABIT	Regular routine
HABIT	If one's broken, that's often good
HABIT	Behavioral pattern

HABIT	Equestrian's attire
HABIT	Attire for an abbess
HABIT	Acquired behavior pattern
HABIT	Riding attire
HABIT	Nun's garb