Last letter in most plurals (but not in this puzzle's six longest answers, which are the only plurals in this grid)

Question:

Answer:

ESS

Length:

Similar Crossword Questions:

Three-letter combinations hidden in this puzzle's six other longest answers
Letter that begins and ends this puzzle's six longest answers
Number of times the letter 'U' appears in each of this puzzle's eight longest answers
Angle irons graphically represented by four sets of black squares in this grid, and by letter formations starting in the four longest answers
Word separated in this puzzle's six longest answers
Discussion group, and a word that can follow the ends of this puzzle's five longest answers
The starts of this puzzle's three longest answers are shades of it
Tampa Bay team playing in this puzzle's longest answers?
Triatomic gas in a thinning layer ... and, symbolically, what appears in this puzzle's four longest answers
Any of five that begin this puzzle's longest answers
Pet targeted by the first words of this puzzle's four longest answers
Busy one that has made its mark in this puzzle's five longest answers
HBO hit, or a hint to the starts of this puzzle's 11-letter answers
What each of the other four longest answers in this puzzle is
Call hidden in this puzzle's eight longest answers that's apt for May Day?
Popular version of a design principle acronym spelled out by the starts of this puzzle's four longest answers
Word divided in this puzzle's nine longest answers
Driveway stuff (and word that's hidden in this puzzle's four longest answers)
The 2x2 black square near the middle of this puzzle's grid, e.g., which is part of eight answers
Word hidden in this puzzle's longest answers
Off one's rocker, and a hint to what the four longest puzzle answers have in common
Each of the four longest puzzle answers has two pairs of them
"Dough" found in this puzzle's four longest answers
Word hidden backwards in this puzzle's eight longest answers
Child in seven of this puzzle's longest answers