1 Across: Find a new home for a pet (6)
1 Down: Sell again after having bought it (6)

2 Down: A suffix, the jumbled letters of "the" or "het" (3)

3 Down: A large bone in a human heel (8)

4 Down: Used to wash a floor (3)

5 Across: Not causing physical pain (8)
5 Down: Program in Ethics and Health (Harvard University) (1,1,1)

6 Down: A suffix forming a noun from "chaste" (3)

7 Down: Using the left foot more naturally than the right (4-6)

8 Down: Former name for Tokyo, reversal of "ode" (3)

9 Down: Strokes (tennis) (5)

10 Across: A suffix, a rearrangement of the letters of "tee" (3)

11 Across: Efficient Deck Hand (merchant navy) (1,1,1)

12 Across: In a sheepish manner (10)

13 Down: Bella, a shortened form of ... (8)

14 Down: Put in a horizontal position (3)

15 Across: Pamper, wait on by hand and ... (4)

16 Across: In generous amounts (9)

17 Down: Having a tough hard texture like leather (7-4)

18 Across: Unidentified Flying Objects (1,1,1'1)
18 Down: Universal Data Format (1,1,1)

19 Across: Fuss (3)
19 Down: Charges for entry (10)

20 Down: Native of Australia (colloq.) (5)

21 Across: Eating implements (6,3,5)

22 Down: Informal name for Vietnam (3)

23 Down: A cigarette (informal) (3)

24 Across: ..., tammy, or tam-o'-shanter (3)

25 Down: Recommendations for a course of action (7)

26 Across: Her Majesty's Inspector (of Schools, UK) (1,1,1)

27 Across: Complete studies (8)

28 Down: Sow with seed again (6)

29 Down: Advertisements (3)

30 Across: Induce someone to have sex (6)

31 Down: Left over (6)

32 Across: Electron Drift Velocity (1,1,1)

33 Across: Indian reservation of United States Native Americans (US, informal) (3)

34 Across: Allocate or appoint (someone) to a job (6)

35 Down: A leader of an organization; "a ten" spelt backwards (Indian) (4)

36 Across: Treat badly (3-3)

37 Down: Swallows (4)

38 Across: Abbreviation of the Hebrew name Elisha (3)

39 Across: Smallest in number (6)

40 Across: Show contempt for, thumb one's ... (Informal) (4,2)

41 Across: Extents of surfaces (5)