double

Used of homologous chromosomes associated in pairs in synapsis.

Having two meanings with intent to deceive.

“a sly double meaning”

Large enough for two.

“a double bed”

“a double room”

Used of flowers having more than the usual number of petals in crowded or overlapping arrangements.

“double chrysanthemums have many rows of petals and are usually spherical or hemispherical”

Consisting of or involving two parts or components usually in pairs.

“an egg with a double yolk”

“a double (binary) star”

Having more than one decidedly dissimilar aspects or qualities.

“a double (or dual) role for an actor”

“every episode has its double and treble meaning”

Twice as great or many.

“ate a double portion”

“the dose is doubled”

Bend over or curl up, usually with laughter or pain.

“He doubled and vomited violently”

Increase twofold.

“The population doubled within 50 years”

Bridge: make a demand for (a card or suit).

Do double duty; serve two purposes or have two functions.

“She doubles as his wife and secretary”

Hit a two-base hit.

Make or do or perform again.

Someone who closely resembles a famous person (especially an actor).

“he could be Gingrich's double”

A quantity that is twice as great as another.

“36 is the double of 18”

A stand-in for movie stars to perform dangerous stunts.

“his first job in Hollywood was as a double for Clark Gable”

A base hit on which the batter stops safely at second base.

“he hit a double to deep centerfield”

Raising the stakes in a card game by a factor of 2.

“I decided his double was a bluff”

To double the degree.

“his eyes were double bright”