Definition of "latch"

latch¹

/læt͡ʃ/

verb
third-person singular simple present latches, present participle latching, simple past and past participle latched or (obsolete) laught
1. To close or lock as if with a latch.
2. (transitive) To catch; lay hold of.
  Quotations
  Where hearing should not latch them.
  c. 1606 (date written), William Shakespeare, “The Tragedie of Macbeth”, in Mr. William Shakespeares Comedies, Histories, & Tragedies […] (First Folio), London: […] Isaac Iaggard, and Ed[ward] Blount, published 1623, [Act IV, scene iii]

latch²

/læt͡ʃ/

noun
plural latches
1. A fastening for a door that has a bar that fits into a notch or slot, and is lifted by a lever or string from either side.
  Quotations
  The cleverly constructed latch which Clayton had made for the door had sprung as Kerchak passed out; nor could the apes find means of ingress through the heavily barred windows.
  1912 October, Edgar Rice Burroughs, “Tarzan of the Apes”, in The All-Story, New York, N.Y.: Frank A. Munsey Co.; republished as chapter 4, in Tarzan of the Apes, New York, N.Y.: A. L. Burt Company, 1914 June,
2. (electronics) An electronic circuit that is like a flip-flop, except that it is level triggered instead of edge triggered.
3. (obsolete) A latching.
4. (obsolete) A crossbow.
5. (obsolete) That which fastens or holds; a lace; a snare.
  Quotations
  Love will none other birde catch, Though he set either nette or latch(please add an English translation of this quotation)
  c. 1360s (date written), Geffray Chaucer [i.e., Geoffrey Chaucer], “The Romaunt of the Rose”, in [William Thynne], editor, The Workes of Geffray Chaucer Newlye Printed, […], [London: […] Richard Grafton for] Iohn Reynes […], published 1542
6. A breastfeeding baby's connection to the breast.
7. (databases) A lightweight lock to protect internal structures from being modified by multiple concurrent accesses.

latch³

/læt͡ʃ/

verb
third-person singular simple present latches, present participle latching, simple past and past participle latched
1. (obsolete) To smear; to anoint.
  Quotations
  But hast thou yet latch'd the Athenian's eyes With the love-juice , as I did bid thee do?
  c. 1595–1596 (date written), William Shakespeare, “A Midsommer Nights Dreame”, in Mr. William Shakespeares Comedies, Histories, & Tragedies: Published According to the True Originall Copies (First Folio), London: […] Isaac Iaggard, and Ed[ward] Blount, published 1623, [Act III, scene ii]