Dictionary Order & Alphabet
🔒 Log in to trackDictionary order rules
🔒 Log in to trackWords sort letter by letter from the left. At the first position where two words differ, the word with the earlier alphabet comes first — everything after that position is irrelevant. Two refinements decide the tricky cases:
- Prefix rule: if one word runs out of letters while matching the other (SCAN vs SCANTY), the shorter word comes first — an ending acts like a space, and a space precedes every letter. (But SCANDAL vs SCANTY is settled at the 5th letter: D < T, so SCANDAL < SCANTY.)
- No skipping: compare position by position; a later difference never overrides an earlier one.
Method for 5-word arrangements: build the words' common prefixes on paper, sort group by group, then read off the asked slot (first / middle / last).
Detailed notes
One rule runs the whole topic
A real dictionary sorts words letter by letter from the left, and so does every question in this topic. At the first position where two words differ, the word with the earlier letter comes first. That single rule answers every arrangement question — the skill is applying it without getting lost.
The comparison algorithm. To order any group of words:
- Compare the first letters. Words sort into groups by their first letter: all A-words before all B-words, and so on.
- Inside a group, compare the second letters; then the third; keep going until the words separate.
- If one word runs out of letters while matching the other word letter for letter (Cart vs Carton), the shorter word comes first — it is a prefix of the longer one.
Work with paper, not memory: stack the words vertically so the columns line up, then scan column by column. The first column that is not identical splits the group into sub-groups; recurse inside each sub-group.
Two classic traps.
- The later-letter trap: early matches lull you into relaxing. Scant, Scan, Scandal all share S-C-A-N; the decision hides at the fifth letter (t vs nothing vs d). Stay letter-by-letter to the very end.
- The prefix trap: a shorter word that matches a longer one's start always comes before it — Scan before Scant, Play before Player. Options routinely offer the reverse because it 'feels' longer-word-first.
Words with same letters, different order. Angel vs Angle: identical multiset of letters, but the third letter (e vs n) splits them — Angel first. The rule never changes: first differing position, earlier letter wins.
Reading the question direction. "Which comes first / last", "which is third", "which pair is adjacent", "which comes just after X" — all four are the same sort followed by a different lookup. Do the full sort once, number the slots 1-2-3-4-5, and answer any of these variants from the numbered list.
Quick revision
- Sort letter by letter from the left; the first differing letter decides.
- A shorter word that is a prefix of a longer one comes first (Scan → Scant → Scandal).
- Stack words vertically and scan columns — never juggle in your head.
- Same letters, different order: the first differing position still decides (Angel before Angle).
- Sort once, number the slots, then answer 'first / last / third / adjacent' from the list.
Where marks are actually lost. Almost never in the rule — always in execution: a misread letter pair (m/n, r/s), a forgotten prefix, or answering 'first' when the question asked 'last'. The numbered-line habit kills all three: order on paper, read the slot, and reread the question's direction word (first / last / second / middle) before marking.
Types of questions asked
Every way this subtopic shows up in exams — how to recognise it, the formula or logic to use, and a solved example.
Type 1: First differing letter decidesvery common3 practice Q
Two or three words sharing an opening; the question asks which comes first or last.
- Scan letter by letter to the first position where the words differ.
- The earlier letter at that position wins the earlier slot.
- Ignore how long the shared part is — only the first difference matters.
Why it works: dictionary order is exactly lexicographic order on the left-most difference.
Example: Which comes first in the dictionary: Market, Margin or Marble?
All share MAR; 4th letters k / g / b → b earliest → Marble comes first.
Type 2: Shorter prefix sorts firstcommon3 practice Q
One word is exactly the start of another (Sand, Sandwich) — a prefix pair.
- If word A matches word B letter for letter and A has no letters left, A is B's prefix.
- The prefix comes before the longer word.
- Among several extensions, compare the letter right after the stem.
Why it works: a dictionary cannot fit anything between a word and itself, so the short form lists first.
Example: Which of these comes first: Sand, Sandy, Sandwich or Sandal?
Sand is a prefix of the other three → Sand comes first.
Type 3: Deep ties beyond the third lettercommon3 practice Q
4-6 words sharing a long stem where the decision hides at the 4th-6th letter.
- Strip the common stem and write only the tails.
- Sort tails letter by letter; the earliest tail letter takes the earliest slot.
- Prefix tails (empty tail) sort first inside their group.
Why it works: the comparison rule does not care how deep the difference hides.
Example: Arrange Sure, Surge, Surgeon, Surplus, Surreal. Which comes third?
4th letters: e / g / g / p / r → Sure, Surge, Surgeon, Surplus, Surreal → third = Surgeon.
Type 4: Slot lookups: middle and adjacent pairscommon2 practice Q
After sorting, the question asks for the middle word or an adjacent pair rather than first/last.
- Produce the full numbered order first — never answer adjacent questions by instinct.
- Middle of 5 words = slot 3; of 4 words, slots 2 and 3 share the middle.
- Adjacent = slot numbers differing by exactly 1.
Why it works: every lookup variant reads off the same sorted list.
Example: Arrange Melon, Melody, Mellow, Member. Which two are adjacent in the dictionary?
4th letters: b / l / l / o → Member, Mellow, Melody, Melon. Adjacent pair: Melon and Melody.
Shortcut tricks
⚡ Find the first split point
Write the words one under another and slide a finger left to right until the letters first differ. That single column decides the entire comparison — ignore all later letters.
Example: Q. Order: SIGN, SIGHT, SIGNAL.
Sol. All start SIG. 4th letters: N, H, N → SIGHT (H) before the rest; SIGN vs SIGNAL: SIGN is a prefix → SIGN first. Order: SIGHT, SIGN, SIGNAL.
The first differing letter settles everything; prefix pairs end shortest-first.
Where students lose marks
Judging words by length instead of first-difference.
Putting SCANDAL after SCANTY because 'scanty feels later' — compare D vs T.
Forgetting the prefix rule: the shorter of two prefix words leads.
Practice sets — 12 questions
Sets of 10, mixed across the question types above. Each answer comes with a step-by-step explanation.
Topic test · 12 questions
Suggested time 9 min · wrong answers go to your mistake notebook automatically.