Answer:

TRI

Answer	Crossword Clue
TRI	Angular lead-in
TRI	A beginning for cot or angle
TRI	Angle or cycle starter

TRI	Corn opener
TRI	Corn or angle starter
TRI	Cycle start
TRI	Numerical prefix
TRI	Sect or cycle starter
TRI	Borough leader to Gothamites
TRI	Cycle starter?
TRI	Pod or angle starter

TRI	Quang .., Vietnam
TRI	TNT component
TRI	Angle lead-in
TRI	Corn or cycle starter
TRI	Cycle or meter starter
TRI	Cycle starter
TRI	Beginning for cot or angle
TRI	The first "T" of TNT

TRI	Prefix with -fold or -focals
TRI	Prefix with pod or plane
TRI	...-state area
TRI	Pod opener
TRI	Sect leader?
TRI	Part of TNT
TRI	..-city area
TRI	One below quadri-

TRI	Prefix with angle or cycle
TRI	Numerical comb. form
TRI	Dent or pod starter
TRI	Prefix on dent or corn
TRI	Starter for some athletes?
TRI	TNT's first T
TRI	...-State Region (NYC area)
TRI	Plane or cycle prefix

TRI	Prefix for atomic or valence
TRI	Three: pref.
TRI	Prefix with color
TRI	Half of hexa-
TRI	Half of sex-