shift, session, retention, reactor, congestion: meanings and examples

Learn these 5 words from IELTS Vocabulary set 35. Each entry includes a definition, example sentence, pronunciation, and synonyms. Use the interactive cards above to practice them.

1. shift · noun/ʃɪft/

   a change in position, direction, or focus

   The sudden shift in public opinion regarding climate change has prompted leaders to take action.

   Synonyms: change, movement, transition

   Origin: The word 'shift' comes from Old English 'scyft', which means 'to divide, to distribute, to change', and is related to the Proto-Germanic '*skeftiz'.

2. session · noun/ˈsɛʃ.ən/

   a period during which a group meets for a specific purpose

   The training session was highly beneficial for all participants, providing valuable skills and knowledge.

   Synonyms: meeting, gathering, conference

   Origin: from Old French 'sessio', from Latin 'sessio', from 'sedere' meaning 'to sit'

3. retention · noun/rɪˈtɛnʃən/

   the act of keeping or holding something in a particular place or condition

   The company implemented new strategies to improve employee retention and reduce turnover rates.

   Synonyms: holding, preservation, maintenance

   Origin: from Latin 'retentio', meaning 'a holding back', from 'retinere' which means 'to hold back'

4. reactor · noun/riˈæktər/

   a device or vessel in which a chemical reaction or nuclear reaction occurs

   The engineer carefully monitored the pressure levels inside the nuclear reactor during the test.

   Synonyms: vessel, chamber, apparatus

   Origin: from the Latin 'reactor', meaning 'one who reacts', derived from 'reagere', meaning 'to act back'

5. congestion · noun/kənˈdʒɛs.tʃən/

   a state of excessive traffic or crowding

   During rush hour, the traffic congestion made it nearly impossible to reach the downtown area on time.

   Synonyms: crowding, blockage, jam

   Origin: Derived from the Latin 'congestio', which means 'a bringing together'.