When you lock out somebody or something (or lock something or somebody out) you lock a door or gate so that they cannot leave or enter a room, building or place.
Examples of use:
1. We were locked out of work this morning because the boss forgot the keys. We had to stand around in the cold for an hour.
2. My neighbours arrived home from holiday to find that their daughter had locked them out of the house.
infinitive – lock out
present simple – lock out and locks out
-ing form – locking out
past simple – locked out
past participle – locked out
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