ETYM Latin constrictio: cf. French constriction.
1. A narrowing that reduces the flow through a channel; SYN. bottleneck.
2. The action or process of constricting or squeezing.
The shortening of two words into one, where an apostrophe is used in place of the omitted letter or letters (I’m, aren’t); or the abbreviation of a word to its first and last letters (Mr, St for “mister”, “street”, “saint”).