
1) Circus hand 2) Deckhand 3) Jack 4) Jack-tar 5) Man of all work on a ranch 6) Mariner 7) Old salt 8) Sea dog 9) Seafarer 10) Seaman 11) Wharf laborer 12) Wharf worker 
Found on 
https://www.crosswordclues.com/clue/roustabout

1) Deckhand 2) Laborer 
Found on 
https://www.crosswordclues.com/clue/roustabout

 An oil `roustabout` refers to a worker who maintains all things in the oil field. He or she sets up oil well `heads,` oil lead lines connected to stock tanks. Roustabouts will maintain saltwater disposal pumps, lease roads, lease mowing, create dykes around tank batteries on a lease, etc. An oil roustabout has no limits in the oil industry and...
Found on 
http://en.wikipedia.org/wiki/Roustabout
[musical]  === User:Shaul avrom=== ...
Found on 
http://en.wikipedia.org/wiki/Roustabout_(musical)

• (n.) A laborer, especially a deck hand, on a river steamboat, who moves the cargo, loads and unloads wood, and the like; in an opprobrious sense, a shiftless vagrant who lives by chance jobs.
Found on 
http://thinkexist.com/dictionary/meaning/roustabout/

a worker on an offshore rig who handles the equipment and supplies that are sent to the rig form the shore base. The head roustabout is very often the crane operator. a worker who assists the foreman in the general work around a producing oilwell, usually on the property of the oil company. A helper on a well servicing unit. 
Found on 
http://www.encyclo.co.uk/visitor-contributions.php
Roust'a·bout`  noun [ Etymol. uncertain.] A laborer, especially a deck hand, on a river steamboat, who moves the cargo, loads and unloads wood, and the like; in an opprobrious sense, a shiftless vagrant who lives by chance jobs. [ Western U.S.] 
Found on 
http://www.encyclo.co.uk/webster/R/98

Drill crew members who handle the loading and unloading of equipment and assist in general operations around the rig.
Found on 
http://www.oilandgasuk.co.uk/glossary.cfm
  No exact match found.