Cognate

In the colloquial sense, cognates are any words in different languages that sound similar and have similar meanings. This may be due to languages borrowing from each other (e.g., English 'ignite' from Latin 'ignis'), acquiring by inheritance from a common parent (English 'man' and German 'Mann'), or by complete coincidence (English 'dog' and Mbabaram 'dog').

Technically (in linguistics) cognates (or 'true' cognates) are only words that spring from common ancestors. They have no obligation to sound alike or have similar meanings. For example, the proto-Indo-European stem *ka:-ro- developed into Latin 'ca:rus' meaning 'dear' (from which we get words like 'charity' and 'cherish'). In English the same word *ka:-ro- developed into the word 'whore'. *ka:-mo-, a different form of *ka:- than *ka:-ro-, went through Sanskrit, ultimately leading to the Kama Sutra.

In biochemistry, this term refers to two biomolecules that typically interact (e.g., a receptor and its ligand).

From the BioTech Dictionary at http://biotech.icmb.utexas.edu/. For further information see the BioTech homenode.

Cog"nate (?), a. [L. cognatus; co- + gnatus, natus, p. p. of nasci, anciently gnasci, to be born. See Nation, and cf. Connate.]

1.

Allied by blood; kindred by birth; specifically Law, related on the mother's side.

2.

Of the same or a similar nature; of the same family; proceeding from the same stock or root; allied; kindred; as, a cognate language.

© Webster 1913.

Cog"nate, n.

1. Law

One who is related to another on the female side.

Wharton.

2.

One of a number of things allied in origin or nature; as, certain letters are cognates.

© Webster 1913.