| It may be filled with helium |
BLIMP |
| It's found near acorns |
OAKLEAF |
| Its square root is itself |
ONE |
| Julius Caesar's undoer |
BRUTUS |
| Lifeline removed from the latest season of 'Who Wants to Be a Millionaire' |
FIFTYFIFTY |
| Like some cars or textbooks |
USED |
| Lower digit |
TOE |
| Make really happy |
ELATE |
| Marx and Engels' 1848 work, e.g. |
MANIFESTO |
| Mesozoic, for one |
ERA |
| Monogram part: Abbr. |
INIT |
| More, in Managua |
MAS |
| Muscle twitch |
SPASM |
| Narrow viewpoint, so to speak |
MYOPIA |
| Orbital station that broke up in 2001 |
MIR |
| Ovine admission |
BAA |
| Pin site |
LAPEL |
| Popular Facebook word game removed due to copyright violation |
SCRABULOUS |
| Prefix before 'potent' or 'present' |
OMNI |
| Qatar's peninsula |
ARABIAN |
| Ramirez who played Pedro in 'Napoleon Dynamite' |
EFREN |
| Record for an individual athlete at a single Olympic Games that remained unbroken until 2008 |
SEVENGOLDMEDALS |
| Relaxation destination |
SPA |
| Richie Rich's metallic, robotic maid |
IRONA |
| Saudi Arabian city home to Muhammad's burial place |
MEDINA |
| Seattle team that became the Oklahoma City Thunder in 2008 |
SUPERSONICS |
| Sesqui- doubled |
TRI |
| Shuttlecock path |
ARC |
| Singer/actress Lena |
HORNE |
| Slew |
DIDIN |
| Sop up |
ABSORB |
| Space explosion |
SUPERNOVA |
| Sri ___ |
LANKA |
| Walk-on role |
CAMEO |
| Warm, so to speak |
NEAR |
| Water, in Waterloo |
EAU |
| What's missing (and likely retired) from 2008's version of Clue |
THELEADPIPE |