KEYSTONE · Day 17

Sunday, August 9, 2026 — three word bridges.

Every neighbouring pair has to make one word. SOME → DAY → LIGHT → HOUSE works because someday, daylight and lighthouse are all words. You are given the two ends; you supply the middle. More than one bridge is often legal, and any legal bridge counts.

Warm-up · written by Kimi K3

PASS????????BACK

4 letters, then 4 letters.

Show an answer

WORD · PLAY

password · wordplay · playback — at least 4 different legal bridges exist for this one, so a different answer may well have counted too.

Main · written by GPT-5

STOP????????HOUSE

5 letters, then 3 letters.

Show an answer

WATCH · DOG

stopwatch · watchdog · doghouse — other legal bridges may also count.

Challenge · written by veritybutnotjoke

SOFT????????WAY

4 letters, then 4 letters.

Show an answer

BALL · PARK

softball · ballpark · parkway — other legal bridges may also count.

How day 17 worked out

Day 17 ran on Sunday, August 9, 2026. Its three bridges were PASS to BACK, STOP to HOUSE and SOFT to WAY. Between them they build nine compound words, all listed at the bottom of this page. Below is the answer to each bridge and what makes it fit.

Warm-up: PASS to BACK

The answer is WORD then PLAY, which gives password, wordplay and playback. The first gap is 4 letters, the second is 4.

This bridge is not unique. KEYSTONE accepts 4 different pairs here and every one of them scores: OVER · COME, OVER · PAY and OVER · THROW work just as well as the pair above. Ends like these sit in the crowded part of the compound-word network, which is why several routes cross them.

Main: STOP to HOUSE

The answer is WATCH then DOG, which gives stopwatch, watchdog and doghouse. The first gap is 5 letters, the second is 3.

Only one pair in the KEYSTONE word bank joins STOP to HOUSE, so this bridge had a single accepted answer. The narrow end is usually the one to solve first.

Challenge: SOFT to WAY

The answer is BALL then PARK, which gives softball, ballpark and parkway. The first gap is 4 letters, the second is 4.

Only one pair in the KEYSTONE word bank joins SOFT to WAY, so this bridge had a single accepted answer. The narrow end is usually the one to solve first.

Every compound word in day 17

BALL has a page listing every compound built on it and the other chains you can run through it.

Every one of those nine compounds turns on a hinge word doing double duty. If you want to see the whole set KEYSTONE draws from, the reference list of 141 compound word hinges gives the words that attach in front of and behind each one.

Play day 17 yourself