What's the difference between a 'crossing' and a 'crossroads'?

As an adjective crossing is (rare) extending or lying across; in a crosswise direction.

As a verb crossing is.

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Crossroad

Crossing 

Noun

(en noun)

• A crossroads (place where one road crosses another)
• A road that crosses another

Noun

(en noun)

• An intersection where roads, lines, or tracks cross
• A place at which a river, railroad, or highway may be crossed
• A voyage across a body of water
• (architecture) The volume formed by the intersection of chancel, nave and transepts in a cruciform church; often with a tower or cupola over it
• Movement into a crossed position.
• * 1989 , Stephen N. Tchudi, ?Diana D. Mitchell, Explorations in the Teaching of English (page 270)
• For example, experts in kinesics — body language — recognize that a person sends out hundreds of nonverbal signals — eyebrow twitches, frowns, leg crossings and uncrossings — every second while he or she is speaking and listening.

Adjective

• (-)
• (rare) Extending or lying across; in a crosswise direction.

Verb

• (head)

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