Originally Posted by
trailangel
[h=2][SUP]1[/SUP]stretch[/h] verb \ˈstrech\: to make (something) wider or longer by pulling it
: to become longer or wider when pulled
[h=2][SUP]1[/SUP]elon·gate[/h] verb \i-ˈlȯŋ-ˌgāt, (ˌ)ē-, ˈē-ˌ\: to make (something) longer or to grow longer
Thank you for the semantics lesson. In practical bicycle mechanics usage, "stretch" implies that the individual strands get longer by deforming plastically, which they don't, they just get closer together. The term "chain stretch" is also considered a misnomer as the metal doesn't get longer by deformation, the chain elongates by wear on the pins and rollers which increases the spacing between links.
So while the dictionary considers them as synonyms and nearly identical in meaning, their use here is differentiated.