Ju"gu*lar (?), a. [L. jugulum the collar bone, which joins together the shoulders and the breast, the throat, akin to jungere to yoke, to join: cf. F. jugulaire. See Join.]

1. (Anat.) (a) Of or pertaining to the throat or neck; as, the jugular vein. (b) Of or pertaining to the jugular vein; as, the jugular foramen.

2. (Zoöl.) Having the ventral fins beneath the throat; -- said of certain fishes.

Ju"gu*lar, n. [Cf. F. jugulaire. See Jugular, a.]

1. (Anat.) One of the large veins which return the blood from the head to the heart through two chief trunks, an external and an internal, on each side of the neck; -- called also the jugular vein.

2. (Zoöl.) Any fish which has the ventral fins situated forward of the pectoral fins, or beneath the throat; one of a division of fishes (Jugulares).

• vein through the neck (or thorax) that returns blood from the head back towards the heart. Properly this is called the jugular vein
  
• By extension any critical vulnerability ("it was vicious; he went for the jugular").
  
• relating to or located near the neck or throat.