understand

For the verb: "to understand"

Simple Past:	understood
Past Participle:	understood

Concise Oxford English Dictionary © 2008 Oxford University Press:
understand/ʌndəˈstand/

▶verb (past and past part. understood)

• 1 perceive the intended meaning of (words, a speaker, or a language).

  ■ perceive the significance, explanation, or cause of.

  ■ interpret or view in a particular way.

• 2 infer from information received: I understand you're at art school.

  ■ supply (a missing word, phrase, or idea) mentally.

  ■ assume to be the case; take for granted.

• 3 be sympathetically aware of: I understand how you feel.

– derivatives
understander noun.

– origin OE understandan (see under-, stand).