Search:
Search Mode
Natural Language
Find single term
Find any term
Find exact phrase
A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
P
Q
R
S
T
U
V
W
X
Y
Z
clearance
1560s, "action of clearing," from
clear
(q.v.). Meaning "approval, permission" (esp. to land or take off an aircraft) is from 1944, Amer.Eng.; national security sense recorded from 1948; meaning "a clear space" is from 1788.