Code Comparison

What are some words that remain words when 'r's are added to them, and what words do they become?

J

The original attempt.

   words =: (#~ 5 < #@>) 'b' fread '/usr/share/dict/words'
   r =: (#~ ('r' e. >)"0) (#~ ('r' -.@e. _2 {. >)"0) words
   n =: (-.&'rR') &.> r
   r =: r #~ n e. words
   n =: n #~ n e. words
   ({~ 10 ? #) n,.r
┌────────────┬─────────────┐
│evolutionist│revolutionist│
├────────────┼─────────────┤
│pokiness    │porkiness    │
├────────────┼─────────────┤
│emotions    │remotions    │
├────────────┼─────────────┤
│toweled     │troweled     │
├────────────┼─────────────┤
│cedent      │credent      │
├────────────┼─────────────┤
│well-famed  │well-farmed  │
├────────────┼─────────────┤
│boddle      │broddle      │
├────────────┼─────────────┤
│shoved      │shroved      │
├────────────┼─────────────┤
│phatic      │phratric     │
├────────────┼─────────────┤
│factions    │fractions    │
└────────────┴─────────────┘
   #n
2371

BQN

   words ← ((5⊸<≠)¨/⊢) •file.Lines "/usr/share/dict/words"
   #      has r         no r in last 2 chars
   r ← ((>'r'⊸∊¨)/⊢) ((>('r'⊸(¬∘∊)¨ ¯2⊸↑¨))/⊢) words
   n ← ((¬∘∊/⊣)⟜"rR")¨ r
   r ↩ (n ∊ words)/r
   n ↩ (n ∊ words)/n
   ⍉>(10 •rand.Range ≠n)⊸⊏¨ n‿r
 ┌─
 ╵ "scogie"   "scrogie"
   "stammel"  "stammrel"
   "spatling" "spartling"
   "boguing"  "broguing"
   "lakish"   "larkish"
   "bangled"  "brangled"
   "bought"   "brought"
   "libated"  "librated"
   "sticks"   "stricks"
   "desecate" "desecrate"
                          ┘
   ≠n
2371

Lil

 wods:"\n" split "r" drop words:read["/usr/share/dict/words"]
 words:"\n" split words
 still:select word:words@index wod:value
   where (wods in words)&(extract (value like "*r*")&!value like "*er" from words)
   from wods
 table random[still -10]
+-----------------+----------------+
| word            | wod            |
+-----------------+----------------+
| "farcy"         | "facy"         |
| "cyclers"       | "cycles"       |
| "trailing"      | "tailing"      |
| "rull"          | "ull"          |
| "bracken"       | "backen"       |
| "psychrophobia" | "psychophobia" |
| "tyring"        | "tying"        |
| "starves"       | "staves"       |
| "grabblers"     | "gabbles"      |
| "redear"        | "edea"         |
+-----------------+----------------+