mast


Also found in: Dictionary, Thesaurus, Medical, Legal, Acronyms, Idioms, Wikipedia.
Related to mast: Mast cells

mast,

large metal or timber pole secured vertically or nearly vertically in a ship, used primarily for supporting sails and rigging. The mast is as old as sailing vessels, and the oldest sailboats depicted (those of ancient Egypt) had a small mast placed forward and carrying a single sail. The Phoenician bireme had one mast, the Greek trireme had two. Viking ships had one central mast. In the Middle Ages, a topmast was added, fixed to the single mast, to carry more sail; after the 16th cent., topmasts were generally demountable. By that time the building of larger vessels and the desire for greater speed on longer journeys had already brought increase in sails and in the masts—a process that continued until the clipper ships of the middle of the 19th cent. were rushed forward by clouds of sails. Above the topmast was added the topgallant mast and above that the topgallant mast royal. In vessels having more than one mast, a small forward mast is called the foremast and a small mast abaft the mainmast is called the mizzenmast. A platform for lookout on a mast is called a crow's nest. The modern merchant ship often has a mast made of hollow steel tubes, which is used mainly for signaling and for supporting radio antennas and lifts or derricks for cargo. In some modern warships the mast has a steel platform on which are mounted instruments for controlling gunfire.

Mast

 

(tower), a structure consisting of a pole or shaft steadied by guys. The pole is supported by a foundation, and the guys are fastened to anchors.

Masts are used most often as supports for radio, radio-relay, and television antennas and other communication structures. Foundations for poles and anchors may be made of cast-in-place plain concrete or reinforced concrete or built up from precast concrete elements; screw piles are also used. Masts are usually erected with the aid of a climbing crane moving along the pole. Light towers with heights up to 120 m are often assembled on the ground and erected with the aid of a derrick. Masts are designed for the least favorable combination of climatic (and sometimes seismic) loads and the loads imposed by the installed equipment.


Mast

 

a vertical metal or wood structure (spar) mounted on a deck in the longitudinal plane of symmetry of the vessel and used for furling the sails, supporting the derricks (masting sheers), radio antennas, light signals, and flag signals. The lower end of the mast is called the mast heel (or foot of the mast) and the upper part of the mast is called the top, or head. The first mast from the bow of a vessel is called the foremast, the second the mainmast, and the mast nearest to the stern the mizzenmast.

mast

[mast]
(engineering)
A vertical metal pole serving as an antenna or antenna support.
A slender vertical pole which must be held in position by guy lines.
A drill, derrick, or tripod mounted on a drill unit, which can be raised to operating position by mechanical means.
A single pole, used as a drill derrick, supported in its upright or operating position by guys.
(mechanical engineering)
A support member on certain industrial trucks, such as a forklift, that provides guideways for the vertical movement of the carriage.
(naval architecture)
A long wooden or metal pole or spar, usually vertical, on the deck or keel of a ship, to support other spars which in turn support or are attached to sails, as well as derricks.

mast

1. A tower which carries one or more load lines.
2. The load-bearing component of a derrick, or the like.

mast

1
1. Nautical any vertical spar for supporting sails, rigging, flags, etc., above the deck of a vessel or any components of such a composite spar
2. Nautical a hearing conducted by the captain of a vessel into minor offences of the crew
3. before the mast Nautical as an apprentice seaman

mast

2
the fruit of forest trees, such as beech, oak, etc., used as food for pigs
References in periodicals archive ?
They were thus able to conclude that mast cell progenitors did not require stem cell factor.
DLA Piper LLP is serving as legal counsel to Mast and Wilson Sonsini Goodrich and Rosati, P.
Bonferroni test showed a significant difference in the mast cell count between acute appendicitis and chronic appendicitis; there was a significant difference in the mast cell count between chronic appendicitis and appendix not showing features of inflammation.
This is a low-profile mast combining the features of the company's conventional Model 76IR search periscope and its Model 86 optronic mast (see above).
Nonspecific staining and autofluorescence were assessed on mast cells using PE-conjugated isotype-matched controls.
RESULTS: The present study of Mast cell profile in lymph node disorders consists of 122 biopsy specimens received at department of Pathology.
Residents and a councillor have voiced health and safety concerns following the collapse of the mast close to a public footpath.
Timerman said: "The more people using mobile phones in an area, the more masts that are needed.
14) Mast cell disease has been documented in numerous small domestic mammals and occasional reptilian species, including dogs, (15-20) cats, (15,16,21,22) ferrets, (23-26) hedgehogs, (27) a snake, (28) and a chelonian.
In a separate case, jurors who heard evidence in a May 2010 trial in Cottage Grove Municipal Court deliberated just 45 minutes before finding Mast not guilty of groping a teenage girl at a party in 2008.
The committee voted by 12 to three in support of the mast.