To determine which definition of "moorings" best fits its usage in the poem, we need to consider the context in which the word appears.
If "moorings" refers to a physical place where a boat is anchored, then definition 1 would be appropriate. If it describes the physical ropes or anchors, then definition 2 is correct. If it's about the act of securing a boat, definition 3 applies. However, if "moorings" is used metaphorically to refer to beliefs, routines, or supports providing stability or security, definition 4 would be the best fit.
Without the specific context from the poem, I can't definitively choose an answer. However, if the poem uses "moorings" in a metaphorical sense, then the best answer would be:
D. definition 4
If you can provide more context or specific lines from the poem, I can give a more accurate answer.