n. 同义词

[ noun ]
two words that can be interchanged in a context are said to be synonymous relative to that context
<noun.communication>

Synonym \Syn"o*nym\ (s[i^]n"[-o]*n[i^]m), n.; pl. {Synonyms}
(s[i^]n"[-o]*n[i^]mz). [F. synonyme, L. synonyma, pl. of
synonymum, Gr. synw`nymon. See {Synonymous}.]
1. One of two or more words (commonly words of the same
language) which are equivalents of each other; one of two
or more words which have very nearly the same
signification, and therefore may often be used
interchangeably. See under {Synonymous}. [Written also
{synonyme}.]

All languages tend to clear themselves of synonyms
as intellectual culture advances, the superfluous
words being taken up and appropriated by new shades
and combinations of thought evolved in the progress
of society. --De Quincey.

His name has thus become, throughout all civilized
countries, a synonym for probity and philanthropy.
--Macaulay.

In popular literary acceptation, and as employed in
special dictionaries of such words, synonyms are
words sufficiently alike in general signification to
be liable to be confounded, but yet so different in
special definition as to require to be
distinguished. --G. P. Marsh.

2. An incorrect or incorrectly applied scientific name, as a
new name applied to a species or genus already properly
named, or a specific name preoccupied by that of another
species of the same genus; -- so used in the system of
nomenclature (which see) in which the correct scientific
names of certain natural groups (usually genera, species,
and subspecies) are regarded as determined by priority.
[Webster 1913 Suppl.]

3. One of two or more words corresponding in meaning but of
different languages; a heteronym. [Rare]
[Webster 1913 Suppl.]