head

1. [TA] The upper or anterior extremity of the animal body, containing the brain and the organs of sight, hearing, taste, and smell. 2. [TA] The upper, anterior, or larger extremity, expanded or rounded, of any body, organ, or other anatomic structure. 3. The rounded extremity of a bone. 4. That end of a muscle that is attached to the less movable part of the skeleton. SYN: caput [TA]. [A.S. heafod]

- bulldog h. the broad h. with high vault occurring in achondroplasia.

- h. of caudate nucleus [TA] the h. or anterior extremity of the caudate nucleus projecting into the anterior horn of the lateral ventricle. SYN: caput nuclei caudati [TA], anterior extremity of caudate nucleus.

- clavicular h. of pectoralis major muscle [TA] See pectoralis major (muscle). SYN: pars clavicularis musculi pectoralis majoris [TA], clavicular part of pectoralis major (muscle).

- deep h. of flexor pollicis brevis [TA] the h. of short flexor of the thumb that arises from the trapezoid and capitate bones and transverse carpal ligaments. It is innervated by the deep ulnar nerve, and considered by many to be the first palmar interosseous muscle. SYN: caput profundum musculi flexoris pollicis brevis [TA].

- h. of epididymis [TA] the upper and larger extremity of the epididymis. SYN: caput epididymidis [TA], caput epididymis, globus major.

- h. of femur [TA] the hemispheric articular surface at the upper extremity of the thigh bone. SYN: caput femoris [TA], caput ossis femoris, h. of thigh bone.

- h. of fibula [TA] the superior extremity of the fibula, which articulates by a facet with the undersurface of the lateral condyle of the tibia. SYN: caput fibulae [TA], upper extremity of fibula.

- hourglass h. in congenital syphilis, a skull with depressed coronal suture.

- humeral h. [TA] the name applied to the heads of forearm muscles that attach to the humerus. Terminologia Anatomica lists humeral heads (caput humerale...) of the following: 1) flexor carpli ulnaris (... musculi flexoris carpi ulnaris [TA]); 2) pronator teres (... musculi pronatoris teretis [TA]); and 3) extensor carpi ulnaris (...musculi extensoris carpi ulnaris [TA]). SYN: caput humerale [TA].

- humeroulnar h. of flexor digitorum superficialis muscle [TA] the h. of the superficial flexor of the digits that attaches to both the humerus and the ulna. SYN: caput humeroulnare musculi flexoris digitorum superificialis [TA].

- h. of humerus [TA] the upper rounded extremity fitting into the glenoid cavity of the scapula. SYN: caput humeri [TA].

- lateral h. [TA] h. of origin farthest from the midline. Terminologia Anatomica lists lateral heads (caput laterale...) of the following: 1) triceps brachii (... musculi tricipitis brachii [TA]); 2) gastrocnemius (... musculi gastrocnemii [TA]); and 3) flexor hallucis brevis (...musculi flexoris hallucis brevis [TA]). SYN: caput laterale [TA].

- little h. of humerus SYN: capitulum of humerus.

- long h. [TA] the h. that has the more proximal origin. Terminologia Anatomica lists long heads (caput longum...) of the following: 1) biceps brachii (... musculi bicipitis brachii [TA]); 2) biceps femoris (... musculi bicipitis femoris [TA]); and 3) triceps brachii (... musculi tricipitis brachii [TA]). SYN: caput longum [TA].

- h. of malleus [TA] the rounded portion of the malleus articulating with the body of the incus. SYN: caput mallei [TA].

- h. of mandible [TA] the expanded articular portion of the condylar process of the mandible. SYN: caput mandibulae [TA].

- medial h. [TA] the h. of origin closest to the midline. Terminologia Anatomica lists medial h. (caput mediale) of the following: 1) triceps brachii (... musculi tricipitis brachii [TA]); 2) gastrocnemius (... musculi gastrocnemii [TA]); and 3) flexor hallucis brevis (... musculi flexoris hallucis brevis [TA]). SYN: caput mediale [TA].

- Medusa h. SYN: caput medusae.

- h. of metacarpal [TA] the expanded distal end of a metacarpal that articulates with the proximal phalanx of the same digit. SYN: caput ossis metacarpalis [TA].

- h. of metatarsal [TA] the expanded distal end of a metatarsal bone that articulates with the proximal phalanx of the same digit. SYN: caput ossis metatarsalis [TA].

- oblique h. [TA] h. of origin which is diagonally situated. Terminologia Anatomica lists oblique heads (caput obliquum...) of the following: 1) adductor hallucis (... musculi adductoris hallucis [TA]); and 2) adductor pollicis (... musculi adductoris pollicis [TA]). SYN: caput obliquum [TA].

- optic nerve h. SYN: optic disk.

- h. of pancreas [TA] that portion of the pancreas lying in the concavity of the duodenum. SYN: caput pancreatis [TA].

- h. of phalanx (of hand or foot) [TA] the rounded articular surface at the distal end of the proximal and middle phalanx of each finger and toe. SYN: caput phalangis (manus et pedis) [TA].

- h. of radius [TA] the disk-shaped upper extremity articulating with the capitulum of the humerus. SYN: caput radii [TA].

- h. of rib [TA] the rounded medial extremity of a rib that, except for ribs 1, 10, 11, and 12, articulates by two facets with the bodies of two contiguous vertebrae. SYN: caput costae [TA].

- saddle h. SYN: clinocephaly.

- short h. [TA] for a muscle with two heads of origin (a “biceps” muscle), the h. originating nearest the insertion. See short h. of biceps brachii, short h. of biceps femoris. SYN: caput breve [TA].

- short h. of biceps brachii [TA] h. of biceps brachii originating from coracoid process of scapula. SYN: caput breve musculi bicipitis brachii [TA].

- short h. of biceps femoris [TA] part of biceps femoris originating from linea aspera of distal half of femur. SYN: caput breve musculi bicipitis femoris [TA].

- h. of stapes [TA] the portion of the stapes that articulates with the lenticular process of the incus. SYN: caput stapedis [TA].

- sternocostal h. of pectoralis major (muscle) [TA] portion of pectoralis major (muscle) originating from the sternum and ribs; acting alone the ternocostal part extends the arm at the shoulder joint; acting with the clavicular h. it adducts the arm. See pectoralis major (muscle). SYN: pars sternocostalis musculi pectoralis majoris [TA], sternocostal part of pectoralis major muscle.

- superficial h. of flexor pollicis brevis [TA] the h. of the short flexor of the thumb that arises from the transverse carpal ligament (flexor retinaculum) and the trapezium. It is innervated by the recurrent branch of the median nerve. SYN: caput superficiale musculi flexoris pollicis brevis [TA].

- h. of talus [TA] the rounded anterior portion of the talus articulating with the navicular bone. SYN: caput tali [TA].

- h. of thigh bone SYN: h. of femur.

- transverse h. [TA] h. of origin of a muscle that is transversely situated. Terminologia Anatomica lists transverse heads (caput transversum...) of the following: 1) adductor hallucis (... musculi adductoris hallucis [TA]); and 2) adductor pollicis (... musculi adductoris pollicis [TA]). SYN: caput transversum [TA].

- h. of ulna [TA] the small rounded distal extremity of the ulna articulating with the ulnar notch of the radius and the articular disk. SYN: caput ulnae [TA].

- ulnar h. [TA] the name applied to a h. of origin of a forearm muscle arising from the ulna. Terminologia Antomica lists ulnar heads (caput ulnare...) of the following: 1) flexor carpi ulnaris (... musculi flexoris carpi ulnaris [TA]); 2) pronator teres (... musculi pronatoris teritis [TA]); and 3) extensor carpi ulnaris (... musculi extensoris carpi ulnaris [TA]). SYN: caput ulnare [TA].

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head 'hed n

1) the division of the human body that contains the brain, the eyes, the ears, the nose, and the mouth also the corresponding anterior division of the body of various animals including all vertebrates, most arthropods, and many mollusks and worms

2) HEADACHE

3) a projection or extremity esp. of an anatomical part: as

a) the rounded proximal end of a long bone (as the humerus)

b) the end of a muscle nearest the origin

c) the anterior end of an invertebrate: SCOLEX

4) the part of a boil, pimple, or abscess at which it is likely to break

5) the end of a lipid molecule that consists of a polar group and is regarded as being opposite to the tail

head adj

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n.

1. the part of the body that contains the brain and the organs of sight, hearing, smell, and taste.

2. the rounded portion of a bone, which fits into a groove of another to form a joint; for example, the head of the humerus or femur.

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(hed) [A.S. hēafod] 1. caput (def. 1). 2. the upper, anterior, or proximal extremity of a structure or body. See also caput.