1. verb be [biː] (reduced [bɪ]); (beest⁽¹⁾, am, art⁽²⁾, is, was, wast⁽³⁾, wert⁽⁴⁾, were; participle I and gerund: being; participle II: been)⁽⁵⁾.
   1. exist, live:
      • I think, therefore I am.
      • There is no doubt about it.
   2. stay, reside, remain, continue:
      • Where are my books?
      • Are you often in town?
      • I have never been to the Caucasus.
   3. happen, occur:
      • Admission exams are once a year in autumn.
   4. amount to:
      • 2 and 2 is 4.
      • 2 times 5 is 10.
   5. linking verb in the nominal predicate:⁽⁶⁾ appear, represent
      • He is a teacher.
      • I am not happy with your behavior.
   6. as an auxiliary verb serves⁽⁷⁾:
      1. for the formation of the continuous aspect:
         • I am reading.
      2. for the formation of the passive voice:
         • Such questions are settled by the committee.
   7. as a modal verb expresses obligation, opportunity, intention⁽⁸⁾:
      • I am to inform you.
      • He is to be there now.
   8. as a part of complex words: future:
      • mum-to-be (future mom)

• noun being [bi:ɪŋ]:
  1. existence:
     • Social being determines consciousness.
  2. creature, essence:
     • human beings – people

• so be it
• to be an hour late

From Old English 'beon', 'beom', 'bion'. The form 'am' from Old English 'eom' (remain)

• Phrasal Verbs with 'Be'