A type of sound change when a sound (especially a vowel) lengthens(noun)
Present participle of lengthen.(verb)
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Use "lengthening" in a sentence
"It sounds counter-intuitive, but extending the term lengthening the lease might solve your current problems with the lease."
"A little perspective and a dollop of humility will go a long way in lengthening a career."
"And luckily, my biggest error to date was regarding CC's "term lengthening to three terms" meaning "a life time pension" for those who go the distance, when it is actually means "a life time of 'Health Care' benefits"."