Y

yellow - ad. having the color like that of gold or the sun

yes - ad. used to express agreement or to permit¹

yesterday - n. the day before today

yet - ad. at some time before now ("Have they arrived yet?"); now; at this time ("I cannot tell you about it yet."); conj. however ("The sun was shining, yet it was cold.")

you - pro². the person or persons being spoken to

young - ad. in the early years of life; not old