There’s a whole word of possibilities imperfect rhymes can add to your lyrics. Imperfect rhymes are rhymes that have the same vowel sound, but a different consonant sound after the vowel sound. The words “dark” and “heart” are imperfect rhymes for that reason. This is unlike perfect rhymes which have the same consonant sound after their vowel sound, like “lap” and “map.”
Depending on how close the consonants are at the end of two words, imperfect rhymes can either be used for lyrics that are complete, balanced, and happy, or for lyrics that are not those things. You have to trust your ear when it comes to how close imperfect rhymes sound to a perfect rhymes. Let’s look at a couple of examples.
Before we met I was in the dark
Now there’s a spotlight on my heart
“Dark” and “heart” are pretty close. They share the “r” before their final consonant, and the “k” and the “t” that they end on are both hard sounds that match pretty decently. So using this rhyme in lieu of a perfect rhyme, for a happy lyric feels appropriate. Especially considering that when these lines are sung, the vowel will probably be held out more than when we speak them, so less focus will be on the consonant that the words end with.
You may be thinking that you want to stick to only perfect rhymes for complete, balanced lyric ideas. But the truth is, if you start to introduce imperfect rhymes into your choices, you’ll open up a much wider range of rhymes to pick from, giving your lyric a much better chance of being interesting, and not cliché.
On the other hand, check out these lines:
I just want to escape
I hope you feel the same
“Escape” and “same” are pretty distant imperfect rhymes. The vowel sound connects them, but that’s about it. The consonant sounds that follow the vowel don’t sound anything alike. The plosive “p” in “escape” isn’t anything like the nasal “m” in “same.” So this rhyme works well for a lyric that implies the idea of longing. The rhyme leaves us longing a more definitive rhyming match. This is good, because it plays into what the lyric is saying.
Imperfect rhymes can range anywhere from having an almost complete feeling to having an almost unstable feeling, and anywhere in between. In addition to that, we have additive and subtractive rhymes, where a word that ends on a vowel is rhymed with a word that ends on a consonant. These types of rhymes are truly middle of the road rhyme types. They usually don’t feel too complete, but they don’t feel too unbalanced either. So use them accordingly.
Let’s look at another example:
Look all I’ve seen
Across the world I’ve roamed
Then you left me
And now I’m feeling broken
In this case, “seen” and “me” are subtractive rhymes (since the consonant is subtracted at the end of the second word), so they’re sort of sitting on the fence in terms of connecting the two words together. “Roamed” and “broken” on the other hand, are pretty different. The “m + ed”” sound in “roamed” is pretty different from the “k + en” consonant sounds in “broken.” Plus “roamed” is a single syllable rhyme that’s being rhymed with the two-syllable word, “broken.” It creates some dissonance between those two lines, which is fitting. The lyric is about feeling broken, and the rhyme is supporting that idea. At the same time, the words “seen” and “me” aren’t creating as many waves, being subtractive rhymes. They’re just kicking back, waiting for “roamed” and “broken” to really deliver the bad news.