syn-, sy-, sym-, syl-, sys-

(Greek: with, together with; also by extension: united; same, similar; at the same time)

acrocephalopolysyndactyly (s) (noun), acrocephalopolysyndactylies (pl)
Any of four heritable malformation syndromes recognizable at birth and characterized by premature craniosynostosis, syndactyly, and polydactyly; also: acrocephalopolysyndactylia.
acrocephalosyndactylia (s) (noun), acrocephalosyndactylias (pl)
Craniostenosis characterized by acrocephaly and syndactyly (fusion of fingers and toes), probably occurring as an autosomal dominant trait and usually as a new mutation.

Acrocephalosyndactylia refers to the premature closure of "cranial sutures" resulting in malformation of the skull. The cranial sutures refer to a type of fibrous joint between the bones of the head.

acrocephalosyndactyly (s) (noun), acrocephalosyndactylies (pl)
An inherited disorder causing abnormalities of the skull, the face, and the hands and feet: In acrocephalosyndactyly, there is closure too-early of some of the sutures of the skull (craniosynostosis).

This acrocephalosyndactyly results in an abnormally shaped head, which is unusually tall and peaked, and an abnormally shaped face with shallow eye sockets and underdevelopment of the midface. There is also a fusion of fingers and toes (syndactyly) and the broad ends of the thumbs and big toes.

acrosyndesis (noun), acrosyndeses (pl)
In genetics, a pairing activity of homologous chromosomes at meiosis that involves the terminal portions of the chromosomes.
ansynchronous (adjectivre), more ansynchronous, most ansynchronous
Conveying something that is not coinciding in time or not corresponding in time.
antagonistic symbiosis, antipathetic symbiosis
A type of symbiosis that is beneficial to one symbiont and detrimental to another one; for example, "parasitism".
archisynagogue, archsynagogue (s) (noun); archisynagogues, archsynagogues (pl)
The ruler of a synagogue.
asymbolia (s) (noun), asymbolias (pl)
The loss of the ability to comprehend the symbolic meanings of things; such as, words, figures, gestures, and signs: Harry's asymbolia made him incapable of understanding previously familiar symbols and signs; usually, because of a lesion in his brain which is a pathological or traumatic damage of brain tissue.
asymmetrical (adjective), more asymmetrical, most asymmetrical
1. Pertaining to something that is not balanced or regularly arranged on opposite sides of a line or around a central point.
2. A reference to something that is lacking equality, balance, or harmony and so not having the same shape and size on both sides.
3. In chemistry, a reference to a carbon atom which has four different atoms or structural groups attached to it, resulting in an unbalanced spatial arrangement of atoms in a molecule, so that the molecule cannot be superimposed on its mirror image.
4. In electrical engineering, relating to varying conductivity or a description of a substance or a device that exhibits varying or different conductivities for electric currents flowing through it in different directions.
5. Referring to an aircraft which is unbalanced because of an unequal thrust from two or more sources; such as, when one engine of a pair is not functioning properly.
asymmetry (s) (noun), asymmetries (pl)
A lack or absence of parts that are the same or similar in form or structure: When Dr. Spock checked the X-ray, he was surprised to see the asymmetry of the corresponding parts of body organs that were on the opposite sides of Steven's body which were normally alike.
asymphytous (adjective), more asymphytous, most asymphytous
Pertaining to being separate or distinct; not grown together: The toes of the rare specimen were asymphytous and therefore it was unable to swim.
asymptomatic (adjective), more asymptomatic, most asymptomatic
Without any sensations or having no changes in bodily functions that are experienced by a patient and is associated with a particular disease: After several physical examinations, the doctor determined that Mildred had no asymptomatic indications of any ailments.
asymptote (s) (noun), asymptotes (pl)
1. A straight line that a curve continually approaches, but never meets, even if the curve is extended to infinity: In a classic picture illustrating perspective, the parallel rails of a railroad are asymptote in that they never intersect.
2. Etymology: from Greek asymptotos, "not falling together", from a-, "not" + syn "with" + ptotos, "fallen"; from piptein, "to fall".
asymptotic (adjective), more asymptotic, most asymptotic
1. Referring to something that is not falling together.
2. With reference to a formula, becoming increasingly exact as a variable approaches a limit, usually infinity: That which is coming into consideration as a variable approaches a limit, usually infinity; such as, asymptotic property; asymptotic behavior.
asynchronism (s) (noun), asynchronisms (pl)
1. Relating to something that is operating at a rate determined by the system rather than at a regular rate of chronological time; without a fixed time pattern: The injection of the new medication was supposed to correct the asynchronism of Kim's nerve impulses.
2. Describing the relationship of two or more systems that run at their own rates and interact at unpredictable times: Despite practicing for weeks, Sharon's jumping jack, or toy figure of a man with jointed limbs that can be moved by pulling attached strings, appeared to be resulting in asynchronisms or uncoordinated movements.

Inter-related cross references, directly or indirectly, involving word units dealing with "equal, identical, same, similar": auto-; emul-; equ-, equi-; homeo-; homo-; iso-; pari-; peer; rhomb-; tauto-.