| 100% | MARTIAN | 7 | Sci-fi alien |
| 94% | ETS | 3 | Sci-fi aliens, familiarly |
| 94% | ETS | 3 | Sci-fi aliens: Abbr. |
| 93% | UFO | 3 | Sci-fi alien spacecraft: Abbr. |
| 92% | ETS | 3 | Sci-fi aliens, for short |
| 88% | UFO | 3 | Sci-fi vehicle for aliens |
| 88% | HUMANOID | 8 | Like many sci-fi aliens |
| 83% | HALO | 4 | Sci-fi video game franchise with militaristic aliens |
| 83% | UFO | 3 | Alien sci-fi vehicle: Abbr. |
| 80% | STARGATE | 8 | 1994 sci-fi film about an alien artifact |
| 79% | CONEHEADS | 9 | 1993 sci-fi comedy with pointy-skulled aliens |
| 77% | ETS | 3 | Alien crew in sci-fi films |
| 75% | HIVE | 4 | ___ mind, sci-fi phrase that refers to a collective alien intelligence |
| 71% | AVATAR | 6 | Sci fi film that went really big |
| 70% | UFO | 3 | Alien spacecraft in a sci-fi film, say: Abbr. |
| 70% | STARTREK | 8 | Sci fi series with Captains Kirk, Picard, Janeway |
| 68% | DANIELX | 7 | Sci-fi series, cowritten by 16-Across, whose title hero is an alien teenage boy: 2 wds. |
| 68% | HRGIGER | 7 | Swiss artist known for his design of the creature in 1979 sci-fi film Alien |
| 68% | SKY | 3 | "Fire in the ___," 1993 sci-fi movie centered around a man's alien abduction experience |
| 67% | CIRCLE | 6 | 2015 sci-fi movie where aliens abduct 50 people who awaken in a darkened room |
| 66% | MEN | 3 | "___ in Black," 1997 sci-fi film starring Tony Shalhoub as an alien arms dealer, Jack Jeebs |
| 66% | STARWARS | 8 | Mega sci fi movie franchise began in 1977 |
| 64% | BIONIC | 6 | The __ Woman, 70s sci fi show about Jaime Sommers |
| 62% | KIND | 4 | "The Fourth ___," 2009 sci-fi movie where a psychologist uncovers a series of alien abductions through her patients |
| 60% | PREDATOR | 8 | "Alien vs. ___" (2004 sci-fi movie) |
| 59% | LIFE | 4 | "Another ___," sci-fi drama series about space that follows a crew of astronauts as they investigate a mysterious alien artifact |
| 59% | MARSATTACKS | 11 | 1996 sci-fi film directed by Tim Burton, with Jack Nicholson as a president facing an alien invasion: 2 wds. |
| 59% | SAUCER | 6 | Sci-fi transport |
| 59% | ROBOTS | 6 | Sci-fi servants |
| 59% | ETS | 3 | Sci-fi regulars |