Synonyms for Twin:

adj.

biform (adjective)
bi-form.
double (adjective)
double-faced, twinned, double, twice, two, bifurcated, bilateral, dual, two-sided, dualistic, two-faced, second, dyadic, bi-form, binary, duplex, duplicate, duple, two-fold, paired, double-barreled.
duplicate, similar (adjective)
coupled, parallel, matched, double, identical, matching, corresponding, like, binary, Duplicating, second, accompanying, twofold, copied, dual, paired, same.
identical (adjective)
indistinguishable, Duplicating, duplicate, same, fellow, alike, copied, coupled, equivalent, interchangeable, accompanying, identical, twofold.
like (adjective)
such.
similar (adjective)
close, Resembling, akin, ersatz, such, like, semblance, similar, alike, comparable, imitative, analogous, uniform.
twofold (adjective)
duplex.

n.

intimate, inseparable, related, fellow, allied, companion, interrelated, connected, interdependent, synonymous, involved, corresponding. bairn, baby, foundling, bundle of joy, babe, babe in arms, designer baby, blue baby, infant, feeder. friendly, friend, intergovernmental, the global village, exchange, multination, the international community, friendship, international relations, multinational. duplication (noun)
bifurcation, duo.
similarity (noun)
analog, alikeness, sameness, analogy, similarity, match, resemblance, closeness, similitude, likeness, imitation.
something exactly like another (noun)
counterpart, duplicate, likeness, match, companion, mate.
twin (noun)
gemini, pair, matched, twinned, matching, similitude, siamese, match, counterpart, similar, parallel, duplicate, twin falls, mate, couple.

v.

stative (verb)
duplicate, parallel.

Other synonyms:

companion. fellow.

Usage examples for twin

  1. How am I ever going to get that other twin – Baby Mine by Margaret Mayo
  2. As I listened, I seemed"- the old man's look glowed suddenly-" to see the two great leaders, the two foes of a century ago, standing side by side, twin brethren in a new battle, growing out of the old, with a great mingled host behind them." – The Case of Richard Meynell by Mrs. Humphrey Ward
  3. It consists of a square base of sides thirty- five feet wide, broken by six rows of twin arches; the first, the third and the sixth are open, the last is a belfry. – Cathedrals of Spain by John A. (John Allyne) Gade