1. [syn: on guard, on one's guard(p), upon one's guard(p), on your guard]
The Collaborative International Dictionary of English v.0.48:
Guard \Guard\, n. [OF. guarde, F. garde; of German origin; cf.
OHG. wart, warto, one who watches, warta a watching, Goth.
wardja watchman. See Guard, v. t.]
1. One who, or that which, guards from injury, danger,
exposure, or attack; defense; protection.
His greatness was no guard to bar heaven's shaft.
2. A man, or body of men, stationed to protect or control a
person or position; a watch; a sentinel.
The guard which kept the door of the king's house.
3. One who has charge of a mail coach or a railway train; a
4. Any fixture or attachment designed to protect or secure
against injury, soiling, or defacement, theft or loss; as:
(a) That part of a sword hilt which protects the hand.
(b) Ornamental lace or hem protecting the edge of a
(c) A chain or cord for fastening a watch to one's person
(d) A fence or rail to prevent falling from the deck of a
(e) An extension of the deck of a vessel beyond the hull;
esp., in side-wheel steam vessels, the framework of
strong timbers, which curves out on each side beyond
the paddle wheel, and protects it and the shaft
(f) A plate of metal, beneath the stock, or the lock
frame, of a gun or pistol, having a loop, called a
bow, to protect the trigger.
(g) (Bookbinding) An interleaved strip at the back, as in
a scrap book, to guard against its breaking when
5. A posture of defense in fencing, and in bayonet and saber
6. An expression or admission intended to secure against
objections or censure.
They have expressed themselves with as few guards
and restrictions as I. --Atterbury.
7. Watch; heed; care; attention; as, to keep guard.
8. (Zool.) The fibrous sheath which covers the phragmacone of
Note: Guard is often used adjectively or in combination; as,
guard boat or guardboat; guardroom or guard room; guard
Advanced guard, Coast guard, etc. See under Advanced,
Grand guard (Mil.), one of the posts of the second line
belonging to a system of advance posts of an army.
(a) A boat appointed to row the rounds among ships of war
in a harbor, to see that their officers keep a good
(b) A boat used by harbor authorities to enforce the
observance of quarantine regulations.
Guard cells (Bot.), the bordering cells of stomates; they
are crescent-shaped and contain chlorophyll.
Guard chamber, a guardroom.
Guard detail (Mil.), men from a company regiment etc.,
detailed for guard duty.
Guard duty (Mil.), the duty of watching patrolling, etc.,
performed by a sentinel or sentinels.
Guard lock (Engin.), a tide lock at the mouth of a dock or
Guard of honor (Mil.), a guard appointed to receive or to
accompany eminent persons.
Guard rail (Railroads), a rail placed on the inside of a
main rail, on bridges, at switches, etc., as a safeguard
Guard ship, a war vessel appointed to superintend the
marine affairs in a harbor, and also, in the English
service, to receive seamen till they can be distributed
among their respective ships.
Life guard (Mil.), a body of select troops attending the
person of a prince or high officer.
Off one's guard, in a careless state; inattentive;
unsuspicious of danger.
On guard, serving in the capacity of a guard; doing duty as
a guard or sentinel; watching.
On one's guard, in a watchful state; alert; vigilant.
To mount guard (Mil.), to go on duty as a guard or
To run the guard, to pass the watch or sentinel without
Syn: Defense; shield; protection; safeguard; convoy; escort;
care; attention; watch; heed.
WordNet (r) 3.0 (2006):
adj 1: vigilant; "on guard against con artists"; "must remain on
your guard in such a situation" [syn: on guard, on
one's guard(p), upon one's guard(p), on your guard]
Moby Thesaurus II by Grady Ward, 1.0:
53 Moby Thesaurus words for "on guard":
Argus-eyed, all ears, all eyes, at bay, aux abois, aux aguets,
canny, careful, cautious, circumspect, custodial, defensively,
deliberate, discreet, eagle-eyed, gingerly, guarded, hawk-eyed,
heedful, hesitant, in defense, in self-defense, judicious,
keen-eyed, leaving out nothing, lidless, mindful, noncommittal,
observant, on the defensive, on the lookout, on the watch,
open-eyed, overlooking no possibility, pawky, politic, prudent,
regardful, safe, sharp-eyed, sleepless, slow to act, tentative,
thorough, unadventurous, uncommunicative, undaring, unenterprising,
unprecipitate, vigilant, wary, watchful, with open eyes