The first stanza and the title refer to the typical "fisherman's tale" about the "one that got away".
In the second stanza, bowing your head refers to either praying or the Asian form of greeting. The mourning reference is to "wringing one's hands".
You can "lend a hand" and "hold someone's hand". In Poker, players show their hands to find who wins or fold their hand if it is no good. The last line refers to the many other uses of the word "hand"!
The hint refers to other usages - bananas grow in hands, a horse's height is measured in hands (4 inches), an assistant may be known as a hand (e.g. stagehand), and someone's particular style of writing can be referred to as their "hand" (e.g. "leftclick has a very scrappy hand").