Noticed some sport* tags:
The sport_* tags:
1) 1 . . . sport_ball
2) 2 . . . sport_center
3) 1 . . . sport_club
4) 4 . . . sport_suit
5) 601 . . . sport_swimsuit
6) 4 . . . sport_top
7) 3 . . . sport_uniform
(and 3 posts . . . sport_utility_vehicle , https://en.wikipedia.org/wiki/SUV )
The sports_* tags:
1) 6 . . . sports_ball (didn't find a Wikipedia article)
2) 23 . . . sports_bike (Wikipedia article singular https://en.wikipedia.org/wiki/Sport_bike )
3) 67 . . . sports_bikini (closest Wikipedia i can find is "Sports bikinis" at https://en.wikipedia.org/wiki/Bikini#In_sport )
4) 10 . . . sports_bottle (Wikipedia: Sport_bottle redirects to Water_bottle)(implying to water_bottle may be good, checked Amazon and they bottle you can drink from withOUT unscrewing top)
5) 8471 . . . sports_bra , https://en.wikipedia.org/wiki/Sports_bra
6) 10 . . . sports_bra_bikini
7) 4 . . . sports_bra_lift
8) 2 . . . sports_cap
( 9) 99 . . . sports_car , https://en.wikipedia.org/wiki/Sports_car )
10) 1 . . . sports_club_kobold
11) 16 . . . sports_drink
12) 1 . . . sports_equipment
13) 1 . . . sports_festival
14) 3 . . . sports_gloves
15) 25 . . . sports_jersey
16) 9 . . . sports_leotard
17) 1028 . . . sports_mask
18) 8 . . . sports_outfit
19) 75 . . . sports_pads
20) 527 . . . sports_panties
21) 1 . . . sports_panties_aside
22) 1 . . . sports_skirt
23) 3 . . . sports_stadium
24) 60 . . . sports_tape
25) 5 . . . sports_team
26) 7 . . . sports_top
27) 84 . . . sports_uniform
with above overlaps of :
a) sport_ball (one post) OR sports_ball (6 posts) : {EDIT: maybe sport_ball ... example: a soccer ball is usually only used in soccer}
b) sport_top (4 posts) OR sports_top (7 posts)
c) sport_uniform (3 posts) OR sports_uniform (84 posts)
sport* general tags:
https://e621.net/tags?commit=Search&search%5Bcategory%5D=0&search%5Bhide_empty%5D=1&search%5Bname_matches%5D=sport%2A&search%5Border%5D=name