| Serious peak | 12 |
| Serious overcharging | 20 |
| Serious or solemn | 17 |
| Serious offense against God | 27 |
| Serious offense | 15 |
| Serious offender | 16 |
| Serious missteps | 16 |
| Serious lineman? | 16 |
| Serious Lewis Carroll topic | 27 |
| Serious lawbreaker | 18 |
| Serious lapses | 14 |
| Serious lapse | 13 |
| Serious lack | 12 |
| Serious investigation | 21 |
| Serious injury from fire | 24 |
| Serious hwy. violation | 22 |
| Serious hostilities | 19 |
| Serious homophone | 17 |
| Serious homebody | 16 |
| Serious heart surgery | 21 |
| Serious hang-ups? | 17 |
| Serious grime | 13 |
| Serious grilling by the cops? | 29 |
| Serious girlfriend | 18 |
| Serious Frisbee thrower? | 24 |
| Serious forgetfulness | 21 |
| Serious flu outbreak, e.g. | 26 |
| Serious flip-flopper | 20 |
| Serious flaw | 12 |
| Serious fight | 13 |
| Serious femme fatale? | 21 |
| Serious fan groups | 18 |
| Serious fan | 11 |
| Serious faculty member when it comes to grading tests? | 54 |
| Serious errors | 14 |
| Serious entertainment | 21 |
| Serious encroachment | 20 |
| Serious elbow-bender | 20 |
| Serious effort | 14 |
| Serious drug cases, for short | 29 |
| Serious drinkers | 16 |
| Serious drinker | 15 |
| Serious downpours | 17 |
| Serious disorder | 16 |
| Serious disloyalty | 18 |
| Serious discussion's lack | 29 |
| Serious depression | 18 |
| Serious demeanor | 16 |
| Serious dating, in personal ads | 31 |
| Serious danger | 14 |
| Serious cut | 11 |
| Serious custom | 14 |
| Serious criminal | 16 |
| Serious crimes | 14 |
| Serious crime | 13 |
| Serious conflicts | 17 |
| Serious conflict | 16 |
| Serious ceremony | 16 |
| Serious ceremonies | 18 |
| Serious Broadway fare | 21 |
| Serious borders? | 16 |
| Serious biker's machine | 27 |
| Serious bacteria | 16 |
| Serious attention | 17 |
| Serious argument components | 27 |
| Serious apprehension | 20 |
| Serious and kind of scary | 25 |
| Serious alarm | 13 |
| Serious ailment | 15 |
| Serious accident | 16 |
| Serious about | 13 |
| Serious | 7 |
| Seriocomic show | 15 |
| Serio-comic show | 16 |
| Serin | 5 |
| Serigraph | 9 |
| Serif-free font | 15 |
| Serif-free character | 20 |
| Serif or souci preceder | 23 |
| Series-shortening abbr. | 23 |
| Series-long story line | 22 |
| Series-ending abbr. | 19 |
| Series-curtailing abbr. | 23 |
| Series-concluding abbr. | 23 |
| Series, in Sevilla | 18 |
| Series' test episode | 24 |
| Series with Smits and Dey | 25 |
| Series with Sergeant Friday | 27 |
| Series with multiple timelines | 30 |
| Series with lots of homicides | 29 |
| Series with detective Mac Taylor | 32 |
| Series with Capt. Picard, to fans | 33 |
| Series with an upcoming Episode VII | 35 |
| Series with a Dey in court | 26 |
| Series with a "Secrets of the Sun" episode | 52 |
| Series with "Duck Amuck" and "One Froggy Evening" | 69 |
| Series winners: 1969 and 1986 | 29 |
| Series winners in 1934 | 22 |
| Series whose title character works for Mode magazine | 52 |
| Series VIP | 10 |