| Iconic "Another Green World" Brian | 44 |
| Iconic "Casablanca" role | 34 |
| Iconic "Seinfeld" role | 32 |
| Iconic British Nigerian soft rock singer | 40 |
| Iconic Japanese island, familiarly | 34 |
| Iconic red draft beer conveyance | 32 |
| Iconoclastic 20th-century journalist | 36 |
| Icons representing users in cyberspace | 38 |
| ID assigned to over 453 million people so far | 45 |
| ID entry for those with but two names | 37 |
| ID for a U.S. permanent resident | 32 |
| ID found in many Amazon.com URLs | 32 |
| ID in the form "xxx-xx-xxxx" | 38 |
| ID issued by the Federated States of Micronesia | 47 |
| ID that can never begin 000 or 666 | 34 |
| ID with nine digits and two hyphens | 35 |
| Ida of ''The Sea Wolf'' | 39 |
| IdaHO's "Niagara of the West" | 43 |
| Idaho's Coeur d'__ River | 32 |
| Idaho's most populous county | 32 |
| Idaho's ___ Percé Indians | 32 |
| Idée ___ (accepted idea, in French) | 38 |
| Idea that may spread via the Internet | 37 |
| Idea that opposes evolution, for short | 38 |
| Ideal condition in which to ford a stream | 41 |
| Ideal for engines and audio equipment | 37 |
| Ideal spacecraft-propulsion method | 34 |
| Idealized American women of the 1890s | 37 |
| Idealized view of a parent, say, in psychology | 46 |
| Ideally, what things should be put to | 37 |
| Ideas generated by two-track minds? | 35 |
| Ideas proposed as demonstrable truths | 37 |
| Identical antagonist in some fiction | 36 |
| Identical offspring, in modern science | 38 |
| Identical to the point of boring | 32 |
| Identical to, with "the" | 34 |
| Identification aid in an obituary | 33 |
| Identified as a closet homosexual | 33 |
| Identified, as an undercover cop | 32 |
| Identifier first issued in 1936: Abbr. | 38 |
| Identifies, as an undercover cop | 32 |
| Identifies, as in a Facebook photo | 34 |
| Identify the coordinates of, e.g. | 33 |
| Identify with another's thoughts | 36 |
| Identify, as with Facebook photos | 33 |
| Identifying line in some Apple ads | 34 |
| Identity thief's acquisitions, for short | 44 |
| Identity thief's pay dirt, briefly | 38 |
| Identity thief's target: Abbr. | 34 |
| Idi Amin or Jean-Claude Duvalier? | 33 |
| Idiom for a multitude of ongoing projects | 41 |
| Idiom for a neologist taking a siesta? | 38 |
| Idiom for an impracticable dream | 32 |
| Idiom for no longer able to function | 36 |
| Idiom for the noblest members of society | 40 |
| Idiom with "as" in the middle | 39 |
| Idiomatic sheep's clothing wearer | 37 |
| Idiot who drove his car into two feet of mud? | 45 |
| Iditarod racer's destination | 32 |
| Idle of ''Spamalot'' | 36 |
| Idle of "Life of Brian" | 33 |
| Idle of "Monty Python" | 32 |
| Idle of "Spamalot" fame | 33 |
| Idle one in the Monty Python crew? | 34 |
| Idle repairman's employer, in ads | 37 |
| Idle who sang "The Lumberjack Song" | 45 |
| Idol Clay currently in "Spamalot" | 43 |
| Idol contestant who came in second to Studdard | 46 |
| Idol of the "Claymates" | 33 |
| Idol whose fans are called Claymates | 36 |
| Idol whose fans are known as Claymates | 38 |
| Idol's disappointing features | 33 |
| IDs often used in identity theft | 32 |
| IDs often verified by the last 4 digits | 39 |
| IDs passed down to Fido by bequest? | 35 |
| Idyllic valley in the Kunlun Mountains | 38 |
| If 50% survives the heat, then...? | 34 |
| If A > B and B > C, then A > C, e.g. | 45 |
| If a = b and b = c, then a = c, e.g. | 36 |
| If all goes exactly according to plan | 37 |
| If any deity were to have a great tan, ___ | 42 |
| If broken, some people are happy, some sad | 42 |
| If everything goes as badly as possible | 39 |
| If follower, in computer programs | 33 |
| If it ain't this, don't fix it | 38 |
| If it blows its top, run through Italy | 38 |
| If it follows also, it's a failure | 38 |
| If it's a bust, it still may qualify as this | 48 |
| If it's a bust, it still qualifies as this | 46 |
| If it's canceled, it has been accepted | 42 |
| If it's canceled, it's accepted | 39 |
| If it's German, it may be a dog | 35 |
| If it's outstanding, it's really not good | 49 |
| If it's repeated, it's nothing new | 42 |
| If it's tidy, it's not tiny | 35 |
| If not today, then tomorrow . . . maybe | 39 |
| If Ohio went the other way, ___ be president now | 48 |
| If one is white, it's no big deal | 37 |
| If one is white, then it's little | 37 |
| If one's broken, it's often good | 40 |