Locks small son in forest perhaps (7)

From Daily Telegraph Cryptic 31236, 21D

21D — Locks small son in forest perhaps (7) — TRESSES

  • Definition
    Definition found: 'Locks'
  • Indicator
    Indicator found: 'in'
  • Operation
    'in' signals a container operation
  • Fodder
    Fodder: 'small son forest'
  • Abbreviation
    Abbreviations spotted: 'small' → S
  • Abbreviation
    Abbreviations spotted: 'son' → S
  • Assembly
    S + S + TREES = TRE(SS)ES

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