noun

• Senses relating to becoming involved with or entering into, especially entering into a contract.
• An act of incurring debt; also (generally), an act of acquiring something (generally negative).
• (archaic) An act of entering into a contract or agreement; specifically, a contract of marriage; a contracting; also (obsolete), a betrothal.
• (biology, medicine) The process of contracting or becoming infected with a disease.
• Senses relating to pulling together or shortening.
• A (sometimes reversible) contracting or reduction in length, scope, size, or volume; a narrowing, a shortening, a shrinking.
• (archaic or obsolete) An abridgement or shortening of writing, etc.; an abstract, a summary; also (uncountable), brevity, conciseness.
• (biology, medicine) A stage of wound healing during which the wound edges are gradually pulled together.
• (biology, medicine) A shortening of a muscle during its use; specifically, a strong and often painful shortening of the uterine muscles prior to or during childbirth.
• (economics) A period of economic decline or negative growth.
• (linguistics) A process whereby one or more sounds of a free morpheme (a word) are reduced or lost, such that it becomes a bound morpheme (a clitic) that attaches phonologically to an adjacent word.
• (linguistics, phonology, prosody) Synonym of syncope (“the elision or loss of a sound from the interior of a word, especially of a vowel sound with loss of a syllable”)
• (orthography) In the English language: a shortened form of a word, often with omitted letters replaced by an apostrophe or a diacritical mark.
• (by extension) A shorthand symbol indicating an omission for the purpose of brevity.
• (obsolete, rare) An act of collecting or gathering.