Jacob's staff

Century Dictionary and Cyclopedia

1. n. A pilgrim's staff.
2. n. A staff concealing a dagger.
3. n. A support for a surveyor's compass, consisting of a single leg, instead of the tripod ordinarily used. This leg is made of suitable wood, shod at one end with a steel point to be stuck in the ground, and having at the other end a brass head with a ball-and-socket joint and axis above. The advantages of the Jacob's-staff are superior lightness and portability; the disadvantages, that it can not be used on rocks or frozen ground or on pavements.
4. n. A cross-staff. The cross-staff was for a long time a most important instrument for navigators, by whom, however, it does not appear ever to have been called a “Jacob's-staff”; bat it was so designated by the Germans (Jakob's Stab), and also in English by some landsmen and poets, as shown by the annexed quotations. See quadrant.
5. n. The group of three stars in a straight line in the belt of Orion, also called the ell-and-yard, our Lady's wand, etc. The leader of the three is δ Orionis, a very white variable star.
6. n. verbascum Thapsus, the common mullen.

GNU Webster's 1913

1. n. [Obs.], (Surveying) See under Staff.
2. n. (Surv.) a single straight rod or staff, pointed and iron-shod at the bottom, for penetrating the ground, and having a socket joint at the top, used, instead of a tripod, for supporting a compass.

WordNet 3.0

1. n. desert shrub of southwestern United States and Mexico having slender naked spiny branches that after the rainy season put forth foliage and clusters of red flowers